Agricultural sampling system and related methods

ABSTRACT

An automated computer-controlled sampling system and related methods for collecting, processing, and analyzing agricultural samples for various chemical properties such as plant available nutrients. The sampling system allows multiple samples to be processed and analyzed for different analytes or chemical properties in a simultaneous concurrent or semi-concurrent manner. Advantageously, the system can process soil samples in the “as collected” condition without drying or grinding. The system generally includes a sample preparation sub-system which receives soil samples collected by a probe collection sub-system and produces a slurry (i.e. mixture of soil, vegetation, and/or manure and water), and a chemical analysis sub-system which processes the prepared slurry samples for quantifying multiple analytes and/or chemical properties of the sample. The sample preparation and chemical analysis sub-systems can be used to analyze soil, vegetation, and/or manure samples.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of PCT ApplicationNo. PCT/IB2019/055862, filed Jul. 10, 2019, which claims the benefit ofpriority to U.S. Provisional Patent Application No. 62/696,271 filedJul. 10, 2018, U.S. Provisional Patent Application No. 62/729,623 filedSep. 11, 2018, U.S. Provisional Patent Application No. 62/745,606 filedOct. 15, 2018, U.S. Provisional Patent Application No. 62/792,987 filedJan. 15, 2019, U.S. Provisional Patent Application No. 62/829,807 filedApr. 5, 2019, U.S. Provisional Patent Application No. 62/860,297 filedJun. 12, 2019. The entireties of all the foregoing listed applicationsare incorporated herein by reference.

BACKGROUND

The present invention relates generally to agricultural sampling andanalysis, and more particularly to a fully automated system forperforming soil and other types of agricultural related sampling andchemical property analysis.

Periodic soil testing is an important aspect of the agricultural arts.Test results provide valuable information on the chemical makeup of thesoil such as plant-available nutrients and other important properties(e.g. levels of nitrogen, magnesium, phosphorous, potassium, pH, etc.)so that various amendments may be added to the soil to maximize thequality and quantity of crop production.

In some existing soil sampling processes, collected samples are dried,ground, water is added, and then filtered to obtain a soil slurrysuitable for analysis. Extractant is added to the slurry to pull outplant available nutrients. The slurry is then filtered to produce aclear solution or supernatant which is mixed with a chemical reagent forfurther analysis.

Improvements in testing soil, vegetation, and manure are desired.

BRIEF SUMMARY

The present invention provides an automated computer-controlled samplingsystem and related methods for collecting, processing, and analyzingsoil samples for various chemical properties such as plant availablenutrients (hereafter referred to as a “soil sampling system”). Thesampling system allows multiple samples to be processed and analyzed fordifferent analytes (e.g. plant-available nutrients) and/or chemicalproperties (e.g. pH) in a simultaneous concurrent or semi-concurrentmanner, and in relatively continuous and rapid succession.Advantageously, the system can process soil samples in the “ascollected” condition without the drying and grinding steps previouslydescribed.

The present system generally includes a sample preparation sub-systemwhich receives soil samples collected by a probe collection sub-systemand produces a slurry (i.e. mixture of soil, vegetation, and/or manureand water) for further processing and chemical analysis, and a chemicalanalysis sub-system which receives and processes the prepared slurrysamples from the sample preparation sub-system for quantification of theanalytes and/or chemical properties of the sample. The describedchemical analysis sub-system can be used to analyze soil, vegetation,and/or manure samples.

In one embodiment, the sample preparation system generally includes amixer-filter apparatus which mixes the collected raw soil sample in the“as sampled” condition (e.g. undried and unground) with water to form asample slurry. The mixer-filter apparatus then filters the slurry duringits extraction from the apparatus for processing in the chemicalanalysis sub-system. The chemical analysis sub-system processes theslurry and performs the general functions of extractant andcolor-changing reagent addition/mixing, centrifugating the slurry sampleto yield a clear supernatant, and finally sensing or analysis fordetection of the analytes and/or chemical properties such as viacolorimetric analysis.

Although the sampling systems (e.g. sample collection, preparation, andprocessing) may be described herein with respect to processing soilsamples which represents one category of use for the disclosedembodiments, it is to be understood that the same systems including theapparatuses and related processes may further be used for processingother types of agricultural related samples including without limitationvegetation/plant, forage, manure, feed, milk, or other types of samples.The embodiments of the invention disclosed herein should therefore beconsidered broadly as an agricultural sampling system. Accordingly, thepresent invention is expressly not limited to use with processing andanalyzing soil samples alone for chemical properties of interest.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein likeelements are labeled similarly and in which:

FIG. 1 is a schematic flow diagram of a soil sampling analysis systemaccording to the present disclosure;

FIG. 2 is flow chart showing the functional aspects of each sub-systemof the sampling analysis system;

FIG. 3 is a top perspective view of a mixing device of the samplepreparation sub-system;

FIG. 4 is a bottom perspective view thereof;

FIG. 5 is an exploded top perspective view thereof;

FIG. 6 is an exploded bottom perspective view thereof;

FIG. 7 is a front view thereof;

FIG. 8 is a first side view thereof;

FIG. 9 is a second opposite side view thereof;

FIG. 10 is a top view thereof;

FIG. 11 is a bottom view thereof;

FIG. 12 is a front cross-sectional view thereof;

FIG. 13 is a side cross-sectional view thereof;

FIG. 14 is a side cross-sectional view of a sample collection/volumizingstation mounted atop the mixing device and comprising an upper pinchvalve in an open position and lower pinch valve in a closed position;

FIG. 15 is a first sequential view thereof showing a soil sample stagedin lower pinch valve for mixing and stopper of the mixing chamber in aclosed position;

FIG. 16 is a second sequential view thereof showing the upper pinchvalve closed;

FIG. 17 is a third sequential view thereof showing the lower pinch valveopen and the soil sample deposited in the mixing device;

FIG. 18 is fourth sequential view thereof showing a second soil samplestaged in the lower pinch valve in standby for mixing;

FIG. 19 is fifth sequential view thereof showing water added to themixing device with the soil sample as indicated by directional flowarrows;

FIG. 20 is a sixth sequential view thereof showing the mixing deviceblending the soil sample and water to prepare a slurry;

FIG. 21 is a seventh sequential view thereof showing the slurry removedfrom the mixing device and water injected into the mixing chamber forcleanout with the stopper of the mixing chamber in an open position;

FIG. 22 is a top perspective view of a second embodiment of a mixingdevice;

FIG. 23 is a bottom perspective view thereof;

FIG. 24 is a rear view thereof;

FIG. 25 is a top view thereof;

FIG. 26 is a bottom view thereof;

FIG. 27 is a top view thereof;

FIG. 28 is an exploded top view thereof;

FIG. 29 is an exploded bottom view thereof;

FIG. 30 is a first side cross-sectional view thereof showing the mixingdevice in a closed position;

FIG. 31 is a second side cross sectional view thereof;

FIG. 32 is a third side cross-sectional view thereof showing the mixingdevice in an open position;

FIG. 33 is a top perspective view of a movable stopper of the mixingdevice of FIG. 22;

FIG. 34 is a bottom perspective view thereof;

FIG. 35 is an enlarged detail taken from FIG. 31;

FIG. 36 is an enlarged detail taken from FIG. 32;

FIG. 37 is an enlarged detail of the stopper and mixing device housinginterface;

FIG. 38 is a top perspective view of a filter retainer usable in thefirst embodiment of the mixing device;

FIG. 39 is a bottom perspective view thereof;

FIG. 41 is a side view thereof;

41 is cross-sectional view thereof;

FIG. 42 is a perspective view of a filter coupleable to the retainer;

FIG. 43 is a top perspective view of a first embodiment of a centrifuge;

FIG. 44 is a bottom perspective view thereof;

FIG. 45 is a front view thereof;

FIG. 46 is a rear view thereof;

FIG. 47 is a first side view thereof;

FIG. 48 is a second side view thereof;

FIG. 49 is a top view thereof;

FIG. 50 is a bottom view thereof;

FIG. 51 is a top exploded perspective view thereof;

FIG. 52 is a bottom exploded perspective view thereof;

FIG. 53 is a front cross sectional view thereof;

FIG. 54 is a side cross sectional view thereof;

FIG. 55 is a top perspective view of a fluid exchange dock of thecentrifuge;

FIG. 56 is a bottom perspective view thereof;

FIG. 57 is a top perspective view of a rotary tube hub of thecentrifuge;

FIG. 58 is a bottom perspective view thereof;

FIG. 59 is an exploded perspective view of a centrifuge tube of thecentrifuge for mounting to the tube hub;

FIG. 60 is a first top view thereof;

FIG. 61 is a cross-sectional view taken from FIG. 60;

FIG. 62 is a second top view thereof;

FIG. 63 is a cross sectional view taken from FIG. 62;

FIG. 64 is a top perspective view of a locking cap for the centrifugetube;

FIG. 65 is a bottom perspective view thereof;

FIG. 66 is a top perspective view of a cover assembly for the tube hubshowing the centrifuge tubes in a non-centrifugated vertical position;

FIG. 67 is a view thereof showing the centrifuge tubes in a pivotedcentrifugated horizontal position;

FIG. 68 is a bottom exploded perspective view of the tube hub and fluidexchange dock;

FIG. 69 is a first front perspective view of a piston-movable drivesystem of the centrifuge;

FIG. 70 is a second front perspective view thereof;

FIG. 71 is a side cross-sectional view showing the centrifuge withcentrifuge tubes in a horizontal position;

FIG. 72 is a first cross sectional sequential view thereof showing thecentrifuge and drive mechanism in a non-rotating first upper dockedposition;

FIG. 73 is a second cross-sectional sequential view showing thecentrifuge and drive mechanism in a non-rotating second lower undockedposition;

FIG. 74 is a third cross-sectional sequential view showing thecentrifuge and drive mechanism in a low speed rotating second lowerundocked position;

FIG. 75 is a fourth cross-sectional sequential view showing thecentrifuge and drive mechanism in a high speed rotating second lowerundocked position for centrifugating a slurry sample;

FIG. 76 is an top exploded perspective view of the drive mechanism;

FIG. 77 is a side view of an absorbance analysis cell for performingcolorimetric analysis of a supernatant;

FIG. 78 is a schematic flow diagram of a soil sampling and processingsystem in a first operating mode configuration;

FIG. 79 is a schematic flow diagram of a soil sampling and processingsystem in a second operating mode configuration;

FIG. 80 is a schematic flow diagram of a soil sampling and processingsystem in a third operating mode configuration;

FIG. 81 is a schematic flow diagram of a soil sampling and processingsystem in a fourth operating mode configuration;

FIG. 82 is a schematic flow diagram of a soil sampling and processingsystem in a fifth operating mode configuration;

FIG. 83 is a schematic flow diagram of a soil sampling and processingsystem in a sixth operating mode configuration;

FIG. 84 is a schematic flow diagram of a soil sampling and processingsystem in a seventh operating mode configuration;

FIG. 85 is a schematic flow diagram of a soil sampling and processingsystem in a eighth operating mode configuration;

FIG. 86 is a schematic flow diagram of a soil sampling and processingsystem in a ninth operating mode configuration;

FIG. 87 is a schematic flow diagram of a soil sampling and processingsystem in a tenth operating mode configuration;

FIG. 88 is a schematic flow diagram of a soil sampling and processingsystem in a eleventh operating mode configuration;

FIG. 89 is a schematic flow diagram of a soil sampling and processingsystem in a twelfth operating mode configuration;

FIG. 90 is a schematic flow diagram of a soil sampling and processingsystem in a thirteenth operating mode configuration;

FIG. 91 is a schematic flow diagram of a soil sampling and processingsystem in a fourteenth operating mode configuration;

FIG. 92 is a schematic flow diagram of a soil sampling and processingsystem in a fifteenth operating mode configuration;

FIG. 93 is a schematic flow diagram of a soil sampling and processingsystem in a sixteenth operating mode configuration;

FIG. 94 is a schematic flow diagram of a soil sampling and processingsystem in a seventeenth operating mode configuration;

FIG. 95 is a top cross sectional view of the drive mechanism of themixing device;

FIG. 96 is a top perspective view of a microfluidic processing disk withplurality of chemical processing wedges each configured as a stand aloneprocessing training for performing complete soil slurry processing andchemical analysis;

FIG. 97 is a bottom perspective view thereof;

FIG. 98 is a partially exploded perspective view thereof with fluidexchange dock which fluidly couples to the microfluidic processing diskshown below;

FIG. 99 is a bottom perspective view thereof;

FIG. 100 is a side view of the microfluidic processing disk;

FIG. 101 is a top view thereof;

FIG. 102 is a bottom view thereof;

FIG. 103 is a perspective view of one processing wedge showing its flowconduits and external fluid connections;

FIG. 104 is a schematic flow diagram showing the arrangement of themicrofluidic flow distribution network and its fluidic micro-componentsof a single chemical processing wedge of the microfluidic processingdisk in a first operating mode configuration;

FIG. 105 is a schematic flow diagram thereof in a second operating modeconfiguration;

FIG. 106 is a schematic flow diagram thereof in a third operating modeconfiguration;

FIG. 107 is a schematic flow diagram thereof in a fourth operating modeconfiguration;

FIG. 108 is a schematic flow diagram thereof in a fifth operating modeconfiguration;

FIG. 109 is a schematic flow diagram thereof in a sixth operating modeconfiguration;

FIG. 110 is a schematic flow diagram thereof in a seventh operating modeconfiguration;

FIG. 111 is a schematic flow diagram thereof in a eighth operating modeconfiguration;

FIG. 112 is a schematic flow diagram thereof in a ninth operating modeconfiguration;

FIG. 113 is a schematic flow diagram thereof in a tenth operating modeconfiguration;

FIG. 114 is a schematic flow diagram thereof in a eleventh operatingmode configuration;

FIG. 115 is a schematic flow diagram thereof in a twelfth operating modeconfiguration;

FIG. 116 is a schematic flow diagram thereof in a thirteenth operatingmode configuration;

FIG. 117 is a schematic flow diagram thereof in a fourteenth operatingmode configuration;

FIG. 118 is a schematic flow diagram thereof in a fifteenth operatingmode configuration;

FIG. 119 is a schematic flow diagram thereof in a sixteenth operatingmode configuration;

FIG. 120 is a side cross sectional view of an light emitting diode (LED)emitting diode assembly and LED receiving diode assembly associated withthe flow analysis cell window shown in FIGS. 104-119 for measuring ananalyte;

FIG. 121 is a top cross sectional view thereof;

FIG. 122 is a top perspective view of a standalone absorbance flowanalysis cell;

FIG. 123 is a bottom perspective view thereof;

FIG. 124 is an exploded perspective view thereof;

FIG. 125 is a front view thereof;

FIG. 126 is a side view thereof;

FIG. 127 is a top plan view thereof;

FIG. 128 is a bottom plan view thereof;

FIG. 129 is a front cross-sectional view thereof;

FIG. 130 is front top perspective view of a second embodiment of acentrifuge configured for use with the microfluidic processing disk ofFIG. 96;

FIG. 131 is a bottom rear perspective view thereof;

FIG. 132 is a front exploded perspective view thereof;

FIG. 133 is a rear exploded perspective view thereof;

FIG. 134 is a front view thereof;

FIG. 135 is a side cross sectional view thereof;

FIG. 136 is a detailed view taken from FIG. 135;

FIG. 137 is a front perspective view of a first embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 138 is a rear perspective view thereof;

FIG. 139 is a front exploded perspective view thereof;

FIG. 140 is a rear exploded perspective view thereof;

FIG. 141 is a front view thereof;

FIG. 142 is a rear view thereof;

FIG. 143 is a side view thereof;

FIG. 144 is a side cross-sectional view thereof;

FIG. 145 is a perspective view of a cam ring of the coulter assembly ofFIG. 137;

FIG. 146 is a plan view thereof;

FIG. 147 is an exploded perspective view of the sample collection probeof the coulter assembly of FIG. 137;

FIG. 148 is a perspective view thereof showing the cam track probeactuation mechanism of the cam ring;

FIG. 149A is a side view of the coulter assembly in a first rotationalposition showing the probe in a first open position for collecting asoil sample;

FIG. 149B is an enlarged detail thereof in perspective view;

FIG. 150A is a side view of the coulter assembly in a second rotationalposition showing the probe in the first open position movably embeddedin the ground for capturing a soil sample;

FIG. 150B is an enlarged detail thereof in perspective view;

FIG. 151A is a side view of the coulter assembly in a third rotationalposition showing the probe in the first open position with captured soilsample;

FIG. 151B is an enlarged detail thereof in perspective view;

FIG. 152A is a side view of the coulter assembly in a fourth rotationalposition showing the probe in a second protruding position after thecaptured soil sample is ejected from the probe;

FIG. 152B is an enlarged detail thereof in perspective view;

FIG. 153 is a front perspective view of a second embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 154 is a rear perspective view thereof;

FIG. 155 is a front exploded perspective view thereof;

FIG. 156 is a rear exploded perspective view thereof;

FIG. 157 is a front view thereof;

FIG. 158 is a rear view thereof;

FIG. 159 is a side view thereof;

FIG. 160 is a side cross-sectional view thereof;

FIG. 161 is a perspective view of a sprocket type indexing cam ring ofthe coulter assembly of FIG. 153;

FIG. 162 is a plan view thereof;

FIG. 163 is a side cross sectional view of a sprocket indexing segmentof the cam ring of FIG. 161;

FIG. 164 is a side perspective view thereof;

FIG. 165 is an enlarged cross sectional view of the probe blade, camring, and collection probe assembly;

FIG. 166 is an exploded perspective view of the probe;

FIG. 167 is a plan view showing the probe in an open position forcollecting soil samples;

FIG. 168 is a plan view thereof showing the probe in a closed positionfor not capturing a soil sample or maintaining a captured soil sample;

FIG. 169 is a perspective view of the inner end of the probe andsprocket;

FIG. 170 is a perspective view of the outer end of the probe;

FIG. 171 is a perspective view of the sprocket engaging the indexing camring;

FIG. 172 is an enlarged detail taken from FIG. 171;

FIG. 173A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a first operatingposition;

FIG. 173B is a side view thereof;

FIG. 174A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a second operatingposition;

FIG. 174B is a side view thereof;

FIG. 175A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a third operatingposition;

FIG. 175B is a side view thereof;

FIG. 176A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a fourth operatingposition;

FIG. 176B is a side view thereof;

FIG. 177A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a fifth operatingposition;

FIG. 177B is a side view thereof;

FIG. 178A is a top plan view of the coulter assembly of FIG. 153 withsprocket engaged with the indexing cam ring in a sixth operatingposition;

FIG. 178B is a side view thereof;

FIG. 179 is a front perspective view of a third embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 180 is a rear perspective view thereof;

FIG. 181 is an exploded perspective view thereof;

FIG. 182 is a front view thereof;

FIG. 183 is a rear view thereof;

FIG. 184 is a side view thereof;

FIG. 185 is a side cross-sectional view thereof;

FIG. 186 is an enlarged view showing the coulter blade and collectionprobe arrangement details;

FIG. 187 is a plan view showing the various rotational positions of thecollection probe as the coulter blade rotates;

FIG. 188 is a plan view showing an alternative variation of the coulterassembly for collecting soil samples at different depths;

FIG. 189 is a rear perspective view of a fourth embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 190 is a front exploded perspective view thereof;

FIG. 191 is a rear view thereof;

FIG. 192 is a front view thereof;

FIG. 193 is a side view thereof;

FIG. 194 is a side cross-sectional view thereof;

FIG. 195 is an enlarged perspective view showing the coulter blade andcollection probe arrangement details with collection ports of the probein a closed position;

FIG. 196 is an enlarged perspective view thereof showing the collectionports in an open position for capturing a soil sample;

FIG. 197 is a front perspective view of a fifth embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 198 is a rear perspective view thereof;

FIG. 199 is a front view thereof;

FIG. 200 is a rear view thereof;

FIG. 201 is an enlarged view showing the coulter blade and collectionprobe arrangement details;

FIG. 202 is a side view thereof;

FIG. 203 is a side cross-sectional view thereof;

FIG. 204 is an enlarged perspective view detail showing the collectionprobe in an open position for capturing a soil sample;

FIG. 205 is a view thereof showing the collection probe in a closedposition;

FIG. 206 is an enlarged perspective view detail showing two collectionports of the collection probe in an open position for capturing a soilsample;

FIG. 207 is a front perspective view of a sixth embodiment of a coulterassembly with sample collection apparatus or probe for collecting a soilsample from an agricultural field;

FIG. 208 is a front perspective view of the resiliently flexible camring of the coulter assembly of FIG. 207;

FIG. 209 is a rear perspective view thereof;

FIG. 210 is a front exploded perspective view thereof;

FIG. 211 is a rear exploded perspective view thereof;

FIG. 212 is a side view thereof;

FIG. 213 is a side cross sectional view thereof;

FIG. 214 is a front view thereof;

FIG. 215 is a rear view thereof;

FIG. 216 is a partial cross-sectional view thereof;

FIG. 217 is a front perspective view of a seventh embodiment of acoulter assembly with sample collection apparatus or probe withlaminated blade assembly for collecting a soil sample from anagricultural field;

FIG. 218 is a rear perspective view thereof;

FIG. 219 is a first front exploded perspective view thereof showing fouralternative types of sample collection probes usable together as shownor individually in the coulter assembly;

FIG. 220 is a second front exploded perspective view thereof;

FIG. 221 is a front view thereof;

FIG. 222 is a rear view thereof;

FIG. 223 is a side view thereof;

FIG. 224 is a first side cross-sectional view thereof taken from FIG.221;

FIG. 225 is a second side cross sectional view thereof taken from FIG.221;

FIG. 226 is a first cross-sectional perspective view showing a first setof two types of collection probes;

FIG. 227 is a second cross-sectional perspective view showing a secondset of two other types of collection probes;

FIG. 228 is an enlarged cross-sectional perspective view showing a firsttype of collection probe;

FIG. 229 is an enlarged cross-sectional perspective view showing asecond type of collection probe;

FIG. 230 is an enlarged cross-sectional perspective view showing a thirdtype of collection probe;

FIG. 231 is an enlarged cross-sectional perspective view showing afourth type of collection probe;

FIG. 232 is a side cross-sectional view of the coulter blade showing theforegoing second type of collection probe;

FIG. 233 is a front view thereof;

FIG. 234 is a side cross-sectional view of the coulter blade showing theforegoing first type of collection probe;

FIG. 235 is a front view thereof;

FIG. 236 is a side cross-sectional view of the coulter blade showing theforegoing third type of collection probe;

FIG. 237 is a front view thereof;

FIG. 238 is a side cross-sectional view of the coulter blade showing theforegoing fourth type of collection probe;

FIG. 239 is a front view thereof;

FIG. 240 is a transverse cross-sectional of a portion of the coulterblade showing the foregoing second type of collection probe;

FIG. 241 is a transverse cross-sectional of a portion of the coulterblade showing the foregoing first type of collection probe;

FIG. 242 is a transverse cross-sectional of a portion of the coulterblade showing the foregoing third type of collection probe;

FIG. 243 is a transverse cross-sectional of a portion of the coulterblade showing the foregoing fourth type of collection probe;

FIG. 244A is a perspective view of the coulter blade showing a radialslot for the foregoing second type of collection probe;

FIG. 244B is a view thereof showing the second type of collection probemounted in the slot;

FIG. 245A is a perspective view of the coulter blade showing a radialslot for the foregoing first type of collection probe;

FIG. 245B is a view thereof showing the second type of collection probemounted in the slot;

FIG. 246A is a perspective view of the coulter blade showing a radialslot for the foregoing third type of collection probe;

FIG. 246B is a view thereof showing the second type of collection probemounted in the slot;

FIG. 247A is a perspective view of the coulter blade showing a radialslot for the foregoing fourth type of collection probe;

FIG. 247B is a view thereof showing the second type of collection probemounted in the slot;

FIG. 248A is a perspective of the foregoing second type of collectionprobe;

FIG. 248B is a transverse cross sectional view thereof;

FIG. 249A is a perspective of the foregoing first type of collectionprobe;

FIG. 249B is a transverse cross sectional view thereof;

FIG. 250A is a perspective of the foregoing third type of collectionprobe;

FIG. 250B is a transverse cross sectional view thereof;

FIG. 251A is a perspective of the foregoing fourth type of collectionprobe;

FIG. 251B is a transverse cross sectional view thereof;

FIG. 252 is a top view of a first embodiment of an agriculturalimplement configured to perform soil sampling and analysis according tothe present disclosure;

FIG. 253 is a side view of a second embodiment of an agriculturalimplement configured to perform soil sampling and analysis according tothe present disclosure;

FIG. 254 is a side view of a third embodiment of an agriculturalimplement configured to perform soil sampling and analysis according tothe present disclosure;

FIG. 255 is a top perspective view of a fourth embodiment of anagricultural implement configured to perform soil sampling and analysisaccording to the present disclosure;

FIG. 256 is an exploded perspective view of an on-diskpneumatically-actuated diaphragm micropump mountable in the microfluidicprocessing disk of FIG. 96;

FIG. 257 is a side cross-sectional view thereof showing the micropump inan unactuated position;

FIG. 258 is a view thereof showing the micropump in an actuatedposition;

FIG. 259 is a perspective view of a heated processing wedge of themicrofluidic processing disk of FIG. 96;

FIG. 260 is an exploded view thereof;

FIG. 261 is a flow diagram showing a soil sample processing and analysissystem with micro-porous filter in lieu of a centrifuge for separatingsupernatant from a prepared soil slurry and extractant mixture;

FIG. 262 is a perspective view of one of a porous inline type filter forseparating supernatant from a soil slurry;

FIG. 263 is a flow diagram showing a soil sample processing and analysissystem embodied in the microfluidic processing disk of FIG. 96 with anintegrated micro-porous filter in lieu of a centrifuge for separatingsupernatant from a prepared soil slurry and extractant mixture;

FIG. 264 is schematic diagram of a first embodiment of a vehicle-mountedwater filtration system usable with the soil analysis and processingsystems disclosed herein;

FIG. 265 is schematic diagram of a second embodiment of avehicle-mounted water filtration system usable with the soil analysisand processing systems disclosed herein;

FIG. 266 is schematic diagram of a third embodiment of a vehicle-mountedwater filtration system usable with the soil analysis and processingsystems disclosed herein;

FIG. 267 shows an example of a particulate filter unit which may withthe water filtration systems of FIGS. 264-266;

FIG. 268 is a top perspective view of a rotary supernatant extractionapparatus for extracting supernatant from soil slurry usingcentrifugation;

FIG. 269 is a top exploded perspective view thereof;

FIG. 270 is a bottom exploded perspective view thereof;

FIG. 271 is a bottom view of the fluid plate thereof showing a pluralityof supernatant separation devices formed in the plate;

FIG. 272 is a plan view of a first embodiment of a supernatantseparation device of FIG. 271;

FIG. 273 is a plan view of a second embodiment of a supernatantseparation device of FIG. 271;

FIG. 274 is a plan view of a third embodiment of a supernatantseparation device of FIG. 271;

FIG. 275 is a plan view of a fourth embodiment of a supernatantseparation device of FIG. 271;

FIG. 276 is a partial side cross-sectional of the supernatant extractionapparatus of FIG. 268;

FIG. 277 is a plan view showing sealing features of the supernatantseparation devices;

FIG. 278 is a first enlarged perspective view thereof;

FIG. 279 is a second enlarged perspective view thereof;

FIG. 280 is a top perspective view of the lower clamping plate of thesupernatant extraction apparatus of FIG. 268;

FIG. 281 is a graph depicting actual measured piston displacement vs.compressive force from testing performed on various soil types utilizingthe compression soil testing apparatus shown in FIG. 282;

FIG. 282 is a schematic diagram of a compression soil testing apparatus;

FIG. 283 is schematic diagram of a weigh container for soil testing;

FIG. 284 is a schematic diagram of a volumetric and mass based analysissystem for determining the moisture content of a collected “raw” soilplug or sample;

FIG. 285 is a schematic diagram of a slurry volume measurement device;

FIG. 286 is a side cross sectional view of an alternative embodiment ofa centrifuge for preparing a soil slurry in a first operating position;

FIG. 287 is a view thereof showing a second operating position;

FIG. 288 is a perspective view of a soil weigh container with slidinggate;

FIG. 289 is a schematic diagram of a weighing device in the form of aweigh coil for measuring weight of a prepared soil slurry;

FIG. 290 is a schematic diagram of a tubular weigh container in a firstoperating mode;

FIG. 291 is a view thereof in a second operating mode;

FIG. 292 is a schematic diagram of a teapot shaped weigh container;

FIG. 293 is a schematic diagram showing a first embodiment of avibration frequency response based weighing device for weighing slurry;

FIG. 294 is a schematic diagram showing a second embodiment of avibration frequency response based weighing device for weighing slurry;

FIG. 295 is a schematic diagram of a slurry weigh coil having a movingmagnet type weighing system;

FIG. 296 is a schematic diagram of a slurry weigh coil with quickdisconnect tubing connectors for isolating the weigh coil from effectsof interconnected flow conduits;

FIG. 297 is a schematic diagram of a slurry weigh coil including acustom load cell for weighing the slurry;

FIG. 298 is a schematic diagram of the custom load cell;

FIG. 299 is a side schematic diagram of a first embodiment of anisolation mounting apparatus for a slurry weighing device;

FIG. 300 is a side schematic diagram of a second embodiment of anisolation mounting apparatus for a slurry weighing device;

FIG. 301 is a schematic diagram showing a slurry weigh station; and

FIG. 302 is a schematic system diagram of a programmable processor-basedcentral processing unit (CPU) or system controller for controlling thesystems and apparatuses disclosed herein.

All drawings are not necessarily to scale. Components numbered andappearing in one figure but appearing un-numbered in other figures arethe same unless expressly noted otherwise. A reference herein to a wholefigure number which appears in multiple figures bearing the same wholenumber but with different alphabetical suffixes shall be constructed asa general refer to all of those figures unless expressly notedotherwise.

DETAILED DESCRIPTION

The features and benefits of the invention are illustrated and describedherein by reference to exemplary (“example”) embodiments. Thisdescription of exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. Accordingly, the disclosureexpressly should not be limited to such exemplary embodimentsillustrating some possible non-limiting combination of features that mayexist alone or in other combinations of features.

In the description of embodiments disclosed herein, any reference todirection or orientation is merely intended for convenience ofdescription and is not intended in any way to limit the scope of thepresent invention. Relative terms such as “lower,” “upper,”“horizontal,” “vertical,”, “above,” “below,” “up,” “down,” “top” and“bottom” as well as derivative thereof (e.g., “horizontally,”“downwardly,” “upwardly,” etc.) should be construed to refer to theorientation as then described or as shown in the drawing underdiscussion. These relative terms are for convenience of description onlyand do not require that the apparatus be constructed or operated in aparticular orientation. Terms such as “attached,” “affixed,”“connected,” “coupled,” “interconnected,” and similar refer to arelationship wherein structures are secured or attached to one anothereither directly or indirectly through intervening structures, as well asboth movable or rigid attachments or relationships, unless expresslydescribed otherwise.

As used throughout, any ranges disclosed herein are used as shorthandfor describing each and every value that is within the range. Any valuewithin the range can be selected as the terminus of the range. Inaddition, all references cited herein are hereby incorporated byreferenced in their entireties. In the event of a conflict in adefinition in the present disclosure and that of a cited reference, thepresent disclosure controls.

Chemical can be a solvent, an extractant, and/or a reagent. Solvent canbe any fluid to make a slurry as described herein. In a preferredembodiment, the solvent is water because it is readily available, butany other solvent can be used. Solvent can be used as both a solvent andan extractant. Gas can be any gas. In a preferred embodiment, the gas isair because it is readily available, but any gas can be used.

Test material refers to supernatant, filtrate, or a combination ofsupernatant and filtrate. When used in this description in the specificform (supernatant or filtrate), the other forms of test material canalso be used.

Fluid conveyor can be a pump, a pressure difference, or a combination ofa pump and pressure difference.

FIG. 1 is a schematic flow diagram of the soil sampling system 3000according to the present disclosure. FIG. 2 is a flow chart describingthe functional aspects of each sub-system of the sampling system. Thesub-systems disclosed herein collectively provides complete processingand chemical analysis of soil samples from collection in theagricultural field, sample preparation, and final chemical analysis. Inone embodiment, the system 3000 may be incorporated onboard a motorizedsampling vehicle configured to traverse an agricultural field forcollecting and processing soil samples from various zones of the field.This allows a comprehensive nutrient and chemical profile of the fieldto be accurately generated in order to quickly and conveniently identifythe needed soil amendments and application amounts necessary for eachzone based on quantification of the plant-available nutrient and/orchemical properties in the sample. The system 3000 advantageously allowsmultiple samples to be processed and chemically analyzed simultaneouslyfor various plant-available nutrients.

The soil sampling system 3000 generally includes a sample probecollection sub-system 3001, a sample preparation sub-system 3002, and achemical analysis sub-system 3003. The sample collection sub-system 3001and motorized sampling vehicle are fully described in U.S. patentapplication Ser. No. 15/806,014 filed Nov. 7, 2017; which isincorporated herein by reference, thereby forming an integral part ofthe present disclosure. Sample collection sub-system 3001 generallyperforms the function of extracting and collecting soil samples from thefield. The samples may be in the form of soil plugs or cores. Thecollected cores are transferred to a holding chamber or vessel forfurther processing by the sample preparation sub-system 3002.

The sample preparation sub-system 3002 generally performs the functionsof receiving the soil sample cores in a mixer-filter apparatus 100,volumetric/mass quantification of the soil sample, adding apredetermined quantity or volume of filtered water based on thevolume/mass of soil, and mixing the soil and water mixture to produce asoil sample slurry, removing or transferring the slurry frommixer-filter apparatus, and self-cleaning the mixer-filter apparatus forprocessing the next available soil sample.

The chemical analysis sub-system 3003 generally performs the functionsof receiving the soil slurry from a mixer-filter apparatus 100 ofsub-system 3002, adding extractant, mixing the extractant and slurry ina first chamber to pull out the analytes of interest (e.g. plantavailable nutrients), centrifuging the extractant-slurry mixture toproduce a clear liquid or supernatant, removing or transferring thesupernatant to a second chamber, injecting a reagent, holding thesupernatant-reagent mixture for a period of hold time to allow completechemical reaction with reagent, measure the absorbance such as viacolorimetric analysis, and assist with cleaning the chemical analysisequipment.

The sample preparation and chemical analysis sub-systems 3002, 3003 andtheir equipment or components will now be described in further detail.

Mixer-Filter Apparatuses

FIGS. 3-18 depict a first embodiment of a mixer-filter apparatus 100 ofthe sample preparation sub-system 3002. Mixer-filter apparatus 100 has asubstantially vertical structure and defines a corresponding verticalcentral axis VA1. The apparatus 100 generally includes a mixingcontainer 101 defining an upwardly open internal mixing chamber 102centered in the container, a fluid manifold chassis 120, an electricmotor 121, and a movable piston-actuated stopper assembly 130. Thesecomponents are arranged to define an inline sample processing unit. Amixing element 140 is mechanically coupled to motor 121 and disposed inmixing chamber 102 for producing a sample slurry. Motor 121 may bedisposed inside and supported by a motor housing 126, which may becylindrical in one non-limiting embodiment. Motor housing 126 may befixedly mounted to the underside of manifold chassis 120, and in turnsupports the motor 121 from the chassis. Motor 121 and housing 126 maybe coaxially aligned with central axis VA1 in one embodiment.

In one embodiment, mixing container 101 may have a substantiallycylindrical body. In addition to the upwardly open mixing chamber 102which occupies the upper portion of the container 101, a downwardly opencentered cleanout port 105 is formed in container body which is in fluidcommunication with the mixing chamber to allow the chamber to be cleanedout between samples processes through the container. Container cleanoutport 105 may have a generally hourglass shape in one embodiment anddefines an inwardly inclined or sloped annular seating surface 105 a. Anoutwardly flared section 105 b of cleanout port 105 below the seatingsurface 105 a defines a diametrically narrower throat 105 c between theflared section and seating surface (best shown in FIGS. 12 and 13). Themixing chamber 102 and cleanout port 105 collectively form a verticalfluid passage coaxially aligned with central axis VA1 passing completelythrough the mixing container 101 for flushing and dumping the contentsof mixing chamber 102 between processing soil samples.

Fluid manifold chassis 120 may have a partial-cylindrical body in oneconfiguration with a pair of opposing flat sides 120 a and a pairarcuately curved sides 120 b extending between the flat sides. The flatsides provide a convenient location for mounting the flow inlet andoutlet nozzles 122, 123 and mounting bracket 103 thereto such as viathreaded fasteners (not shown). In other possible configurations,however, the body of chassis 120 may have other shapes includingcompletely cylindrical, rectilinear, polygonal, or have a variety ofother shapes. The configuration of the chassis body is not limiting ofthe invention. The upper surfaces of chassis 120 may be sloped or angledto better shed water and debris when cleaning out the mixing chamber 102of mixing container 101, as further described herein.

Fluid manifold chassis 120 includes a vertically-oriented centralpassageway 124, and opposing inlet and outlet flow conduits 125, 126fluidly coupled to and in fluid communication with the central passage.Central passageway 124 may be coaxially aligned with central axis VA1.The flow conduits 125, 126 may be horizontally and perpendicularlyoriented relative to the vertical central passageway 124 in oneconfiguration. Inlet nozzle 122 is threadably and fluidly coupled to theinlet flow conduit 125. Similarly, outlet nozzle 123 is threadably andfluidly coupled to the outlet flow conduit 125. In one embodiment, thenozzles 122, 123 may have free ends configured for fluid connection toflow tubing. The central passageway 124 and inlet/outlet flow conduits125, 126 may be formed in the body of fluid coupling chassis 120 by anysuitable method, such as drilling or boring in some embodiments.Manifold chassis 120 may be formed of any suitable metallic ornon-metallic material. In one embodiment, chassis 120 may be formed ofmetal such as steel or aluminum.

Referring to FIGS. 5-6 and 12-13, the piston-actuated stopper assembly130 includes a vertically elongated stopper 131 including a top end 131a and bottom end 131 b. Stopper 131 may have a generally cylindricalbody configuration including a diametrically enlarged head 132 formed onthe upper portion which is disposed in mixing chamber 102 of mixingcontainer 101. In one embodiment, the stopper head 132 may be larger indiameter than the diameter of the container cleanout port 105 at throat105 c such that the stopper cannot be axially withdrawn in a verticaldirection downwards from mixing chamber 102. Stopper head 132 isconfigured and operable to form a sealable engagement with the mixingchamber 102 of mixing container 101. More particularly, stopper head 132defines an annular sealing surface 133 which sealingly engages matingannular seating surface 105 a formed in mixing chamber 102 of mixingcontainer 101. An annular seal 134, which may be an elastomeric orrubber O-ring in one embodiment, is mounted on stopper head 132 atsealing surface 133. The O-ring sealingly engages seating surface 105 aof mixing container 101 to form a leak-resistant seal at the bottom ofthe mixing chamber 102 to close the mixing container cleanout port 105.

The cylindrical lower portion of stopper 131 beneath the enlarged head132 may be diametrically narrower than throat 105 c of the mixingcontainer cleanout port 105, thereby allowing the lower portion to passthrough the throat. In one embodiment, the bottom end 131 b of stopper131 may be externally threaded and threadably mounted to the top offluid manifold chassis 120 at central passageway 124. The threadedbottom end 131 b of stopper 131 threadably engages an internallythreaded upper portion of the central passageway 124 (see, e.g. FIGS.12-13).

Stopper 131 further includes a vertically oriented central bore 144coaxially aligned with central axis VA1 and central passageway 124 ofthe fluid manifold chassis 120. Bore 144 extends completely through thestopper 131 from top end 131 a to bottom end 131 b. Central bore 144 isin fluid communication with mixing chamber 102 of container 101 at topand central passageway 124 of the fluid manifold chassis 120 at bottomof the bore.

Motor drive shaft 142 extends through central bore 144 of stopper 131and central passageway 124 of fluid manifold chassis 120 as shown inFIGS. 12 and 13. This forms an annular space or flow passage between thedrive shaft 142 and the central bore 144 and passageway 124. The annularflow passage therefore provides a fluid path from adding water to mixingchamber 102 of mixing container 101, and extracting the fully mixedwater and soil sample slurry from the mixing chamber 102 for furtherprocessing and chemical analysis.

Although stopper 131 and fluid manifold chassis 120 are depicted asseparate discrete components, it will be appreciated that in otherembodiments the stopper and chassis may be integral parts of amonolithic unitary structure cast, molded, and/or machined to providethe features disclosed.

Referring now to FIGS. 5-6 and 12-13, mixing element 140 generallycomprises a blade assembly 141 fixedly mounted atop a vertical motordrive shaft 142 coupled to motor 121. Blade assembly 141 is thereforrotatable with the drive shaft 142. Drive shaft 142 may be coupled tomotor 121 by a shaft seal 142 a and flexible motor coupling assembly 143in one embodiment. Seal 142 a is configured to form a water-tight sealbetween the drive shaft 142 and manifold chassis 120. Drive shaft 142 isrotatably disposed in and extends completely through central bore 144 ofstopper 131 and central passageway 124 of fluid manifold chassis 120.

Blade assembly 141 may be fixedly coupled to the top end of the driveshaft 142 by a threaded fastener in one embodiment. Blade assembly 141is positioned in mixing chamber 102 and comprises a plurality ofupwardly and downwardly angled blades to provide optimum mixing of thesoil and water slurry in the mixing chamber. The blades may be formed ofmetal, and in one embodiment of a corrosion resistant metal such asstainless steel. Other materials may be used.

Blade assembly 141 is axially spaced apart from and positioned above topend 131 a of stopper 131 exposing the top end of drive shaft 142 in themixing chamber 102 of mixing container 101, as shown in FIGS. 12 and 13.This mounting position of the blade assembly also exposes the top ofcentral bore 144 in stopper 131 to the mixing chamber 102 of mixingcontainer 101 for two way fluid flow into/out of the mixing chamber.

In one embodiment, a filter assembly including a partially threadedfilter retainer 145 and a detachable annular filter 146 is provided tofilter the slurry extracted from the mixing chamber 102. FIGS. 38-42show the retainer and filter in isolation. Filter retainer 145 includesa body having a vertical central bore 147 a which communicates with aplurality of circumferentially arranged radial openings 147 b forinjecting water into mixing chamber 102 of container 101, and extractingslurry from the chamber. Bore 147 a communicates with central bore 144of stopper 131 to complete a fluid pathway between the manifold chassis120 and mixing chamber 102. Motor drive shaft 142 is received throughcentral bore 147 a of the retainer. The annular filter 146 comprises anannular screen 146 a disposed between the central bore 147 a and mixingchamber 102. The screen includes a plurality of preselected sizeopenings to filter out larger solids or particles from the soil slurry.Screen 146 a may be in the form of screen mesh with rectilinear openingsin one embodiment. The screen material may be metallic or non-metallic.

Retainer 145 includes a threaded bottom end or stem 148 which isthreadably coupled to an internally threaded upper portion of thestopper central bore 144 (best shown in FIGS. 12-16, and in detail inFIGS. 38-42). The top end 149 of filter retainer is diametricallyenlarged so as to trap the annular filter 146 between it and the top 131a of stopper 131 when the retainer is threaded into the stopper. Filter146 is mounted to retainer 145 and the screen 146 a covers the radialopenings 147 b to filter the slurry extracted from the mixing chamber102. Top end 149 may include a tooling configuration such as a hex(shown) or other shape to facilitate threadably mounting the retainer145 to the stopper 131. It bears noting that the central bore 147 a offilter retainer 145 extends completely through the top and bottom ends149, 148 to allow the drive shaft 142 to pass completely through theretainer, as shown.

Stopper 131 is fixedly coupled to a movable piston assembly 150 whichoperates to actuate and change position of the stopper in unison withthe piston assembly movement. Referring to FIGS. 5-6 and 12-16, pistonassembly 150 includes an annular piston 151, spring 152, springretaining ring 154, and a pair of piston seal rings 153 which in oneembodiment may be elastomeric or rubber O-rings. Piston 151 may have asleeve-like construction and includes bottom and top ends. Piston 151 isslideably received in a downwardly open annular space 155 formed in themixing container 101 between its cylindrical outer sidewalls 101 a andbottom central cleanout port 105. The piston 151 is movable upward anddownwards in annular space 155 between upper and lower positions.

The top of piston 151 may have a diametrically enlarged top rim 157 withoutward facing annual grooves for mounting the pair of seal rings 153.Rim 157 protrudes radially outwards from the body of the piston 151 asshown. One seal ring 153 is an inner seal ring providing an inboard sealbetween the piston and container 101, and the other seal ring 153 is anouter seal ring providing an outboard seal.

The piston spring 152 is received and retained in the annular space 155of mixing container 101 by retaining ring 154 fixedly attached to thebottom of the container. The top end of the spring 152 acts on theunderside of the top rim 157 of piston 151 and the bottom end acts onthe retaining ring 153. Spring 152 biases the piston 151 upwards insideannular space 155 of container 101 to the upper position. In onenon-limiting embodiment, spring 152 may be a helically coiledcompression spring. Other appropriate type springs may be used.

Piston 151 may be supported from and is mechanically coupled to fluidmanifold chassis 120 by a generally U-shaped mounting bracket 103.Bracket 103 in one embodiment may comprise a lower portion formed by apair of transversely spaced apart plate-like legs 103 a fixedly attachedto opposing sides of chassis 120, and a pair of plate-like upwardlyextending arms 103 b fixedly attached to the underside of the piston151. Each leg 103 a may include a transversely open hole 104 toaccommodate inlet and outlet nozzles 122, 123 coupled to chassis 120which extend through the holes. Mounting bracket 103 may be fixedlyattached to the piston 151 and chassis 120 by threaded fasteners 103 din one embodiment (see, e.g. FIG. 11). Other configurations of mountingbrackets and methods of attachment may of course be used.

The combination of the mounting bracket 103 and manifold chassis 120collectively creates a generally rigid mechanical linkage that couplesthe stopper 131 to piston 151. The fluid manifold chassis 120, motor121/motor housing 126, and stopper 131 thus move in unison with thepiston 151 as a singular unit upwards and downwards when the piston 151is actuated. The piston 151 thus acts as an actuator for stopper 131,and is operable to control and change the position of stopper.

In one embodiment, piston 151 may be pneumatically operated bypressurized air. Piston 151 is configured for spring return operation.The annular space 155 of container 101 may be considered to form anannular piston cylinder in which piston 151 moves upwards and downwards.An air exchange port 156 is formed through thecircumferentially-extending outer sidewall 101 a of the container 101and fluidly connects to the top of annular space 155 (see, e.g. FIG.14). Port 156 is in fluid communication with region of annular space 155located above the piston 151.

In operation, piston 151 is normally biased upwards to the upperposition shown in FIG. 16 by spring 152. To move the piston 151 to thelower position in annular space 155 of container 101, pressurized air isintroduced into in the annular space and applied to the piston top rim157 via the air exchange port 156 (see, e.g. FIG. 14 and directional airflow arrows). The air pressure forces the piston downwards, therebycompressing the spring. Air pressure must be continually applied to holdthe piston 151 in the lower position against the biasing action ofspring 152. To return the piston to its upper position, the pressurizedair is bled off annular space 155 in container 101 outwards through theair exchange port 156 (see, e.g. directional flow arrows, FIG. 16). Thespring 152 then urges the piston 151 back upwards to its upperspring-biased position in FIG. 14.

It bears noting that the air exchange port 156 is fluidly connected to apressured source of compressed air such as compressor 3030 and air tank3031 via air supply valve 3032 shown in FIG. 1 via a suitable flowconduit such as flexible and/or rigid hosing or tubing 3021. Tubing 3021may be metallic or non-metallic. In some embodiments, fluoropolymer typeslurry tubing may be used to transport slurry in various places in thesystem due to its inherent non-stick characteristics making it ideal forsoil slurries. FEP (Fluorinated Ethylene Propylene) is a specificexample of one fluoropolymer that may be used. FEP is similar to usingteflon-based PTFE material due to its non-stick characteristics, but FEPis advantageously more transparent and moldable with standard tubingformation practices.

A three-way air valve 155 a with an exhaust port may be fluidly coupledto and located upstream of port 156 (see, e.g. FIG. 19) to eitherpressurize the container annular space 155 or exhaust air to atmospherefrom the annular space.

By actuation of the piston assembly 150, the stopper 131 is axiallymovable in a vertical direction relative to mixing container 101 betweena lower closed position (see, e.g. FIGS. 19-20) and an upper openposition (see, e.g. FIG. 21). In the closed position, the stopper head132 is sealingly engaged with annular seating surface 105 a in containermixing chamber 102. This position closes and blocks the bottom containercleanout port 105. This position corresponds to the lower portion ofpiston 151 in the container 101 (see, e.g. FIGS. 18 and 19).

Conversely, in the open position, the stopper head 132 of stopper 131disengages the seating surface 105 a in container mixing chamber 102.This position corresponds to the upper position of piston 151 (see, e.g.FIG. 21). This position thus opens cleanout port 105 and establishes acleanout flow path for rinsing and cleaning the mixing chamber 102 withfiltered water after mixing and volumizing a soil sample in preparationfor the next soil sample to be mixed and volumized. When the stopperhead 132 is in the open position, an annular shaped cleanout path andzone is created between the stopper 131 and internal walls of the mixingchamber 102 that extends for a full 360 degrees around the stopper.

It bears noting that the fluid manifold chassis 120 attached to stopper131, motor housing 126 (with motor 121 therein) attached to the chassis,and the blade assembly 141 with drive shaft 142 move in unison as asingle unit with the stopper 131 between the lower closed position andupper open position when actuated.

In order to process, stage, and test multiple soil samplessemi-concurrently, an assembly of inline valves and related componentsare provided as shown in FIGS. 14-18. The assembly is further configuredand operable to volumize the soil sample, thereby representing andcollectively forming a sample collection/volumizing station 160-1.Volumizing the sample is used to indirectly quantify the mass of thesample to determine the appropriate amount of water to add in the mixingchamber 102 (i.e. water/soil ratio) to prepare the sample slurry withthe appropriate consistency or viscosity for further processing andchemical testing. In one embodiment, the assembly which defines a samplecollection/volumization station comprises a pair of vertically stackedsqueeze or pinch valves 160 and 161, an intermediate collar 163 definingan inner plenum 162 fluidly coupled between the valves, and avolumization vessel 164. Vessels 164 is a pressure vessel defining aninitial volumization chamber 168 therein of known volume. Chamber 168 isfluidly coupled to a source of pressurized air such as compressor-tankassembly 30, 31 controlled by air valve 167 in tubing 21 at an inletside of the vessel. Chamber 168 is further fluidly coupled to plenum 162via an outlet tube 165 controlled by another air valve 167.

Pinch valves 160, 161 may be air actuated in one embodiment. Pinchvalves are known in the art and commercially available for controllingthe flow of solid materials such as soil. Each pinch valve 160/161includes a valve body 160 a/161 a defining an internal space containinga flexible collapsible diaphragm or sleeve 160 b/161 b as shown. Thesleeves may be made of any suitable elastomeric material, such as forexample rubber, nitrile, butyl, silicon, or others. Each valve 160, 161includes an air exchange port 166 controlled by a three-way air valve169 including an exhaust port at one position. The lower valve 161 issealingly and fluidly coupled to the mixing container 101 and in fluidcommunication with the mixing chamber 102.

In the open position, the sleeves 160 b, 161 b of valves 160, 161 arespaced apart in generally parallel relationship to allow material toflow through the valves (see, e.g. FIG. 14, upper valve 160). To closethe valves, air is injected into the internal space surrounding thesleeve which pressurizes the interior of the valves. This collapses thesleeve into a closed pinched position to seal against itself forblocking the flow of material (see, e.g. FIG. 14, lower valve 161). Toreturn valve 160 for example to the open position, air is bled back offthe internal space surrounding the sleeve 160 b through air exchangeport 166 and exhausted via the exhaust port of three-way valve 169 toatmosphere.

Staging of the soil samples and volumizing the sample (i.e. determiningthe mass or volume of the soil sample via a volume/pressure analysistechnique) will now be briefly described with reference to FIGS. 14-18.This helps identify the proper amount of water to be added to the sampleto produce the desired consistency (water/soil ratio). These preliminaryprocessing steps are completed before preparing the slurry. Referring toFIG. 302, the process shown in FIGS. 14-18 and described below may beautomatically controlled and monitored by a processor-based controlsystem 2800 including a programmable central processing unit (CPU) (e.g.processing system) referred to herein as system controller 2820, such asdisclosed in copending U.S. patent application Ser. No. 15/806,014 filedNov. 7, 2017; which is incorporated herein by reference. As furtherdescribed elsewhere below, system controller 2820 may include one ormore processors, non-transitory tangible computer readable medium,programmable input/output peripherals, and all other necessaryelectronic appurtenances normally associated with a fully functionalprocessor-based controller.

The processing system 2820 may further control operation of themixer-filter apparatus 100 and other portions of sample preparationsub-system 3002, and the operation of chemical analysis sub-system 3003described in detail elsewhere herein. This provides a unified controlsystem for directing and coordinating all operations of the systems andcomponents described herein.

Both pinch valves 160, 161 may initially be in an open position at thestart of the process in some sequences. FIG. 14 next shows the pinchvalves 160, 161 now in a position ready to receive a soil sample (whichmay comprise a blend of one or more cores) from the probe collectionsub-system 3001 (see, e.g. FIG. 1). The lower valve 161 is first closedand the upper valve 160 remains open. If not already pressurized, thevolumization chamber 168 may optionally be “charged” with air at thistime as well to save processing time. The outlet valve 167 fromvolumization vessel 167 is closed during the charging step. The soilsample is next blown into valve 160 using pressurized air from the probecollection sub-system 3001 previously described herein, as shown in FIG.15. The soil is deposited on top of sleeve 161 b of the lower valve 161.

The upper valve 160 is next closed as shown in FIG. 16. This establishesa temporary sealed or trapped predetermined volume containing the soilwhich is referred to herein as a soil “staging chamber” 170 forconvenience. Chamber 170 is fluidly isolated from the mixing chamber 101by closed valve 161. The staging chamber 170 is collectively formed bythe plenum 162 and internal space between the closed sleeves of theupper and lower valves 160, 161. An initial pressure reading Pi of thevolumization chamber 168 is then measured and read by the processingsystem 2820. Pressure readings Pi may be averaged over a short period oftime for accuracy. Next, the outlet valve 167 between the volumizationchamber 168 and staging chamber 170 is opened to admit pressurized airfrom the volumization vessel 164 into the staging chamber. The pressureequalizes between the staging chamber 170 and volumization chamber 168which are in fluid communication now that the outlet valve has beenopened. A final pressure Pf, lower than Pi of the volumization chamber168 alone when pressurized and previously isolated, is then measured andread by the system 2820. Pressure readings Pf may also be averaged overa short period of time for accuracy. Pressure reading Pf represents thecollective pressure measured in the volumes that include the stagingchamber 170, volumization chamber 168, and valving and tubingtherebetween.

The processing system 2820 next automatically indirectly calculates thesoil “mass” equated to a “volume” to determine the proper amount ofwater to add to the mixing chamber for achieving the desired water/soilratio and consistency of the slurry. The volume of the soil may becalculated using Boyles Law: Pi*Vp=Pf(Vp+Vc−Vs) where Vc=Volume of thestaging chamber 170; Vp=Volume of initial volumization chamber 168;Vs=Volume of soil; Pi=Initial pressure of volumization chamber 168; andPf=Final equilibrium pressure of connected volumes of the stagingchamber 170 and volumization chamber 168 as noted above. The equation issolved for Vs to identify the volume of soil in the staging chamber 170to be dumped into the mixing container 101. The processing system 2820then calculates the amount or volume of water to be added based onpreprogrammed water/soil ratios to yield the proper consistency orviscosity of the sample slurry for chemical analysis. It will beappreciated that other possible volumizing methods of the soil samplemay be used.

Once the sample has been volumized, slurry preparation may begin. Asshown in FIG. 17, the lower valve 161 is opened to dump or add the soilsample into mixing chamber 101 of container 101. This eliminates thetemporary staging chamber 170 until the next sample is processed andvolumized. The upper valve 160 remains closed at this point. In order tostage the next waiting sample for slurry preparation, however, the lowervalve 161 may be closed and the upper valve 160 opened to admit the nextsample as shown in FIG. 18. This operation may occur semi-concurrentlywith processing of the first sample in the mixer-filter apparatus 100.

FIG. 19 shows the soil sample “S” in the “as collected” condition fromthe agricultural field which has first been loaded into mixing chamber102 of mixing container 101. At this juncture, the stopper 131 is inlower closed position previously described herein to close the bottomcontainer cleanout port 105. The sample may be comprised of several soilcores in some instances for generating blended sample chemical profilerepresenting an averaged analysis.

Filtered water (FW) is pumped by water pump 3304 (FIG. 1) to themixer-filter apparatus 100 and injected through inlet nozzle 122 (seedirectional arrow) into the fluid manifold chassis 120. The water flowsradially into the central passageway 124, then axially upwards throughthe passageway and central bore 144 in stopper 131, and radially intothe lower region of mixing chamber 102 through the annular filter 146.This fluid introduction location at the bottom of mixing chamber 101helps fluidize soil in the bottom of the chamber (note that for clarity,the figures only show soil above the mixing blade assembly 141recognizing that the soil will actually fill the entire lower portion ofthe chamber). In some implementations of the process, water may be addedfirst to mixing chamber 101 and mixing blade assembly 141 run at a lowidling speed (RPM) before the soil sample is added. The mixing chamber101 is filled with a predetermined volume or amount of filtered water toachieve the desired water/soil ratio (e.g. 4:1, etc.) preprogrammed intoprocessing system 2820 in to produce a slurry (SL) of proper consistencyfor processing and analysis. The amount of water needed is determinedduring the volumizing step at the volumization station previouslydescribed herein.

FIG. 20 next shows the mixing step. The water and soil mixture is beingmixed by the blade assembly 141 which is rotated at a predetermined fullmixing speed (RPM) to quickly and efficiently prepare the sample slurry(SL) of proper consistency. To help achieve thorough and rapid mixing, aplurality of circumferentially spaced apart mixing protrusions 172 maybe provided in mixing chamber 101 which protrude radially inwards intochamber (best shown in FIG. 10). Protrusions 172 interact with mixingblade assembly 141 to promote thorough mixing. In one embodiment, twopairs of diametrically opposed mixing protrusions 172 may be provided;however, more or less protrusions and other arrangements may be used.Protrusions 172 may have a rounded profile in top plan view in oneembodiment as shown.

Once the slurry has been fully mixed, the slurry is extracted from themixing chamber 102 through outlet nozzle 123 under suction from theslurry pump 3333 of the chemical analysis sub-system 3003 (seedirectional flow arrow). Alternatively, a slurry forwarding pump may beadded if required to forward slurry to the slurry pump depending on theflow dynamics of the system. It bears noting that the stopper 131remains in the lower closed position to seal the cleanout port 105 ofthe mixing container 101 during the extraction step. In operation, theslurry generally flows inwards through the centrally-located annularscreen 146 on filter housing 145 into the central bore 144 of stopper131, and axially downwards through the bore and central passageway 124in manifold chassis 120 to the outlet nozzle 123. The annular screen 146has openings sized to preclude soil or other embedded particles from thefield sample (e.g. small stones, etc.) of a predetermined size fromentering the stopper 131 and manifold chassis 120. Because the slurryflows through the annular space or flow passage formed between the motordrive shaft 142 and the central bore and passageway 144, 124, the screenprevents this somewhat constricted flow space from plugging. The slurryextraction step may preferably be performed with the mixing bladeassembly 141 speed reduced to the slower idling speed. Alternatively,the blade assembly may be fully stopped.

It should be noted that during the mixing step, waste sludge comprisedof an agglomeration of fine soil particles primarily builds up againstthe vertical walls surrounding the mixing chamber 102 due to thecentrifugal action of the mixing blades. Extracting the slurry from thelower central portion of the mixing chamber through the annular filter146 advantageously minimizes plugging the filter in contrast to otherpossible slurry extraction locations that might be used along the wallsof the mixing chamber.

FIG. 21 next shows the mixing chamber 102 flushing and cleanout step,which will be briefly described. The stopper 131 is initially still inthe closed position from the slurry extraction step. In oneimplementation of the mixing chamber cleanout process, a two phase flushand rinse may be used to thoroughly clean the chamber. In the firstinitial phase, the mixing blade assembly 141 is run at slow idling speedwhile the stopper 131 is moved from the lower closed position upwards tothe upper open position. This opens container cleanout port 105 atbottom of mixing chamber 102. The stopper 131 is moved via actuation ofthe piston assembly 150 in the manner previously described herein.Flushing water (e.g. filtered water FW) is injected and sprayed into themixing chamber 102 of mixing container 101 through the inlet nozzle 122and screened housing 145 while the cleanout port 105 remains open. Theflushing water follows the flow path indicated by the directional flowarrows form the inlet nozzle 122 to the mixing chamber. A mixture of theflushing water and sludge from chamber 102 flows downwards and outwardsthrough the cleanout port 105 and the 360 degree open cleanout zoneformed by the cleanout port to waste (see directional waste flowarrows). This concludes the initial flushing and rinsing phase.

In the second final flushing and rinsing phase, the mixing chamber 102is reclosed by moving the stopper 131 to the closed position to blockcleanout port 105 while the flushing water continues to be injected intothe mixing chamber. The mixing chamber 105 now begins to briefly fillwith water. The mixing blade assembly 141 speed is increased to fullspeed for a few seconds to entrain any remaining sludge residue clingingto the mixing chamber walls in the water. The mixing chamber cleanoutport 105 is opened again a second time by raising the stopper 131 toflush out the water and sludge mixture. This completes cleaning of themixing chamber 102. It bears noting that both the initial and finalflushing and rinsing phases are completed in rapid succession in a veryshort time within a matter of a few seconds.

Once the mixing chamber 102 has been thoroughly cleaned, stopper 131 isagain returned to the lower closed position via operation of the pistonassembly 150 in preparation to receive and process the next soil samplein line. The foregoing process steps of volumizing the soil sample,mixing the slurry, and cleaning the mixing chamber are summarized inFIG. 2.

Mixer-Filter Apparatus Alternative Embodiment

FIGS. 22-37 depict an alternative embodiment of a mixer-filter apparatus200 which may be used with sample preparation sub-system 3002.Mixer-filter apparatus 200 generally includes a lower mixing container201, an upper mixer housing 203, a vertically movable elastomericstopper 210, and a mixing blade assembly 240 coupled to a motor driveshaft 220 such as via a threaded fastener or other means. Drive shaft220 is coupled to an electric motor 222 for rotating the blade assembly240. Motor 222 is shown only in FIG. 22 for simplicity. The drive shaft220 is centered in the mixer housing 203 and defines a vertical centralaxis VA2 of the mixer-filter apparatus.

Container 201 defines a soil storage cavity 202 for holding a soilsample for mixing (see, e.g. FIGS. 28-29) to prepare the slurry forchemical analysis. Container 201 may be sealingly and detachably coupledto the bottom of mixer housing 203 such as via seals 204 which may be anO-ring in one embodiment to prevent leakage at the interface between thecontainer and upper housing 203. In some embodiments, the floor 201-1 ofcontainer 201 may optionally be movable relative to the container walls201-2 and mixer housing 203 and formed by a piston assembly 201-3 (shownin dashed lines). This allows the soil sample to be raised towards blade420 for enhanced mixing.

The upper mixer housing 203 includes an axial central cavity 207 whichpenetrates and extends between the top and bottom of the housing asshown. Cavity 207 may be substantially circular in transverse crosssection in one embodiment forming inner cylindrical sidewalls 205 bbounding the cavity. In one embodiment, a portion of the sidewalls 205 bmay include flat portion 205 a.

The lower portion of central opening 207 defines a downwardly openmixing cavity 207 a formed below the elastomeric stopper 210 whichcontains the mixing blade assembly 240. Mixing cavity 207 a and soilstorage cavity 202 of soil container 201 collectively define a mixingchamber 205 when the container is coupled to the upper housing 203. Themixing chamber 205 for preparing the slurry mixture of soil and water.Chamber 205 may have a smaller diameter than the upper portion ofcentral cavity 207 forming a stepped transition therebetween thatdefines an annular seating surface 206. The seating surface 206 may bechamfered in one embodiment producing an angled or inclined seatingsurface which is obliquely oriented to central axis VA2. Blade assembly240 is rotatably disposed in the mixing chamber 205.

Housing 203 further includes an inlet port 208 for injecting filteredwater into mixing chamber 205 and a diametrically opposite outlet port209 for extracting slurry. An air vent 208 a which optionally maycomprise a valve is in fluid communication with the inlet port 208 andcentral cavity 207 of housing 203 for expelling air from the cavityprior to the mixing operation. In some embodiments, the entire housingand chamber may be angularly tilted via a rotary coupling 201-4 (see,e.g. FIG. 30) such that the air vent/valve 209 is at a high point insystem and slurry extraction is below water level (to avoid extractingair with the slurry). Inlet port 208 and cleanout port 105 can be asingle port with a three-way valve to control the flow material in andout.

Whereas the mixing blade assembly 41 and drive shaft 142 of mixer-filterapparatus 100 enters the mixing chamber 102 from the bottom, it bearsnoting that the present blade assembly 240 and drive shaft 22 entersmixing chamber 202 from the top. This arrangement advantageouslydecreases the complexity of shaft seals needed to prevent leakage ofwater from the chamber along the drive shaft.

The elastomeric stopper 210 is disposed at least partially in centralcavity 207 of the mixer housing 203 as best shown in FIGS. 28 and 29.Referring additionally to FIGS. 21-23 and 30-32, mixing chamber 205 isformed beneath the stopper 210. Stopper 210 has a generally cylindricalmain body including a top 215, bottom 214, and cylindrical sidewalls 216extending therebetween. A circular central axial passageway 211 extendsaxially between and penetrates the top and bottom surfaces. The bottom214 may be concavely shaped in one embodiment defining an arcuateprofile in transverse cross section to further facilitate thoroughmixing of the slurry. The stopper 210 assembly may also include a lowerdrive shaft ring seal 214 to prevent leakage of fluid from the mixingchamber 205 along the shaft, and an upper collar bearing 221 whichsupports the shaft within the axial central passageway 211 of thestopper.

A radially extending annular sealing flange 213 projects outwards fromthe main body of stopper 210 for forming a seal with sidewalls of thecentral cavity 207 in the mixer housing 203. Flange 213 is pliable andflexible being formed as an integral unitary structural part of theelastomeric stopper 210. In one embodiment, flange 213 may upwardlyflared (upturned) when in an undeformed condition. A retaining ring213-1 locks the flange 213 in place on mixer housing 203. The housingmay include an annular shoulder 213-2 to facilitate engaging the flange(see, e.g. FIG. 37). The flange 213 engages and creates a seal with thesidewalls of the cavity 207. Water may be injected through inlet port208 of housing 203 into the portion of mixing chamber 205 beneath theannular flange 213 of stopper 210 for preparing the slurry. An open airvent 208 a in housing 203 is provided in for expelling air from thechamber beneath the flange 213 of stopper 210 during initial setup ofthe mixer-filter apparatus 200.

Stopper 210 is axially movable upwards and downwards in cavity 207between a lower seated position and an upper unseated position. Thiscreates an openable and closeable annular interface between the stopperand mixer housing 203 for both filtering the slurry and flushing themixing chamber 205 between samples, as further described herein.

The stopper 210 further includes an upwardly open annular space 212which receives a spring 231 therein (see, e.g. FIGS. 30-32). Spring 231may be a helically coiled compression spring in one embodiment. Spring231 is retained in the annular space by a cover plate 230 removablyattached to mixer housing 203. The top end of spring 231 acts on theunderside of the cover plate 230 and its bottom end acts on the stopper210 to bias the stopper to the lower seated position.

The stopper 210 is fixedly coupled to the drive shaft 220 which isturned is rotatably coupled to motor 222 at one end and the mixing bladeassembly 240 forming an inline movable assembly or unit. The stopper 210may be moved between the lower and upper positions by lifting themovable unit such as via raising or lowering a motor mount (not shown).The blade assembly 240 engages the seal 214 embedded in the stopper bodywhich pulls the stopper 210 upwards when the motor is raised. Thisaction in turn compresses spring 231, which acts to force the stopperback downwards to the lower position when the motor is lowered.

According to one unique aspect of the alternate mixer-filter apparatus200, the apparatus is configured to filter large soil particles ordebris (e.g. stones) from the slurry extracted from the mixer withoutthe use of conventional mesh filter screens which may be prone toplugging. Apparatus 200 further provides an openable/closeable filteringinterface which allows the mixing chamber to be flushed and cleanedbetween processing samples.

To provide the filtering and flushing functions, an annular seatingsurface 217 is formed at the bottom of the cylindrical sidewall 216 ofstopper 210. Seating surface 217 may be inclined or angled obliquely tocentral axis VA2. Seating surface 217 is selectably engageable with itsmating seating surface 206 on the mixer housing 203 when the stopper 210moves between the upper unseated and lower seated positions.Accordingly, seating surface 217 has a complementary angle to seatingsurface 206 to form a flat-to-flat interface thereby establishing anannular seating area.

As best shown in FIG. 34, a plurality of radially oriented flow channelsor grooves 218 are formed in seating surface 217 of stopper 210. Thegrooves 218 are circumferentially spaced apart and preferably extend 360degrees around the seating surface 217. When the stopper is in its lowerseated position, seating surfaces 217 and 206 are mutually engaged. Thegrooves 217, however, remain open to create an array of small diameterflow passages through which the slurry can be extracted from mixingchamber 205 via suction from a pump such as slurry pump 3333 (see, e.g.FIG. 1). The slurry flows in a radial direction outwards through thepassages into an annular flow plenum 240 formed in the portion ofhousing central cavity 207 beneath annular flange 213 of stopper 210.From the plenum 240, the slurry flows through the outlet port 209 of themixer housing 203 to the pump. Flow plenum 240 is also in fluidcommunication with the water inlet port 208 for receiving and injectingwater into the mixing chamber 205 in addition to its role for extractingslurry. The diameter of the flow grooves 218 on stopper 210 is selectedto act as a filter which precludes large particles and debris having agreater diameter than the grooves from being extracted with the slurry.

Operation of the stopper 210 for flushing and cleaning the mixingchamber 205 will now be briefly described. FIGS. 30-31, 35, and 37 showthe stopper in the lower seated position. Seating surfaces 217 and 206are mutually engaged forming a closed annular interface 241 between thestopper 210 and mixer housing 203. This seated position performs thefiltering function since the flow grooves 218 remain the only open flowpaths between flow plenum 240 and mixing chamber 205. Once the slurry isprepared and extracted from the mixer-filter apparatus through grooves218, the stopper 210 is raised to the upper unseated position (see, e.g.FIGS. 32 and 36). This disengages seating surfaces 217 and 206, therebyfully opening the annular interface 241 for a full 360 degrees throughwhich flow plenum 240 and mixing chamber 205 are fluid connected. Thestopper 210 need only be raised far enough to form the circumferentiallycontinuous opening between the seating surfaces 206 and 217. When thestopper 210 is raised to the unseated position, the peripheral edge ofthe annular flange 213 remains frictionally engaged with the sidewallsof the mixing chamber 205 and stationary via operation of the retainingring 213-1. As such, the flange 213 will deform and deflect rather thansimply slide upwards along the sidewalls. In the non-limitingillustrated embodiment, the flange 213 may be normally pre-angled in anupturned position (see, e.g. FIG. 31), and changed to a horizontalposition when the flange deforms as the stopper 210 is raised (see, e.g.FIG. 32). In any case, the key point is that the annular interface 214be fully opened for preferably its entire circumference. Cleaning watermay then be injected, mixed, and flushed out of mixing chamber 205 forcleaning mixer-filter apparatus 100, thereby carrying the sludgeoutwards from the chamber to be discharged to waste. This flushing stepalso cleans any flow grooves 218 that might have been plugged by alarger particle or debris when filtering the slurry. Once complete, thestopper 210 is returned to the lower seated position for the next mixingcycle.

In other possible embodiments, the flow grooves 218 may alternatively beformed on annular seating surface 206 of mixer housing 203 and annularseating surface 217 on stopper 210 may have a flat face instead. Stoppermay be formed of any natural or synthetic elastomeric material such asnatural rubber, synthetic butyl rubber or neoprene, or other elastomericmaterials. The remainder of the components of mixer-filter apparatus 200described above may be made of any suitable metallic or non-metallicmaterial.

In some embodiment, the mixer-filter apparatus 200 may be used in anangled position such as for example in a range from about and including30-60 degrees to horizontal. In such a configuration, the inlet port 208and air vent 208 a preferably are positioned at the highest point of themixer-filter apparatus at top.

In some implementations, the mixing container 201 may be raised andlowered into engagement with the mixer housing 203 after the soil sampleis deposited in the container.

Chemical Analysis Sub-System

Referring to FIG. 1, the chemical analysis sub-system 3003 generallyincludes a slurry pump 3333 and mixing coil, a water supply systemincluding a water tank 3302 and pump 3304, an air vent 3306, anextractant system including an extractant tank 3308 and pump 3310, areagent system including a reagent tank 3314 and pump 3316, asupernatant pump 3312 and mixing coil 3318, a centrifuge 3400 includinga dock 3340 and centrifuge tube 3350, and an absorbance analysis cell3320. The foregoing components and system are fluidly coupled togethervia a suitable flow conduits such as without limitation tubing 3021which may be metallic, non-metallic, or a combination thereof. Eachcomponent of the chemical analysis sub-system 3003 and operation of thesub-system will now be further described.

Slurry pump 3333 may be any suitable type pump which is fluidly coupledto either mixer-filter apparatus 100 or alternative mixer-filterapparatus 200. More specifically, pump 3333 may be fluidly coupled tothe mixing chambers 102 or 205 of either mixer-filter apparatus 100 or200 respectively via tubing 3021. Pump 3333 is configured and operableto extract the mixed soil sample slurry from the chamber for chemicalanalysis using sub-system 3003. In one embodiment, slurry pump 3333 maybe a peristaltic positive displacement pump; however, other suitabletype pumps may be used.

Slurry pump 3333 is fluidly coupled to water pump 3304, air vent 3306,and extractant pump 3310 via tubing 3021. Water pump 3304 takes suctionfrom water tank 3302 which holds a reserve or supply of water such asfiltered water in one embodiment for flushing and cleaning the slurrypump piping loop, as further described herein. Air vent 3306 allows pump3333 to draw air into the slurry pump piping loop to aid in cleaning theloop. Extractant pump 3310 takes suction from extractant tank whichholds a supply or reserve of an extractant.

Water pump 3304, extractant pump 3310, reagent pump 3316 and supernatantpump 3313 may also be positive displacement type pumps to regulate theflow of respective fluids provided to the sampling system componentsshown in FIG. 1.

It particularly bears noting at this juncture that FIG. 1 depicts merelya single chemical processing train 3000A of soil sampling system 3000for convenience, which comprises the extractant system, reagent system,supernatant pump 3312, centrifuge tube 3350, mixing coil 3318, andanalysis cell 3320. This processing train 3000A is configured andoperable to extract and analyze the soil slurry for a singleplant-available nutrient or analyte (e.g. potassium, nitrogen,phosphorus, etc.). When implemented, sampling system 3000 in factactually may comprise multiple chemical processing trains (e.g. 3000B,3000C, 3000D, etc.) which operate to extract and analyze multiplenutrients or analytes simultaneously in parallel rather than in apiece-meal series fashion. This advantageously saves processing time andprovides a complete profile of the soil sample for all nutrients oranalytes of interest. Each processing train is served by a single slurrypump 3333, water supply system, air vent 3306, and centrifuge 3400 whichare fluidly coupled to each processing train in a parallel via separateparallel runs of tubing 3021.

Centrifuge 3400 is a central sample processing component of the chemicalanalysis sub-system 3003 of soil sampling system 3000, which provides asingle unit configured for processing multiple slurry samplessimultaneously in parallel for chemical analysis of different nutrientsor analytes. The centrifuge and related appurtenances will now bedescribed in further detail prior to discussing operation of thesampling system.

Referring initially to FIGS. 43-56, centrifuge 3400 includes a supporthousing 3401 generally comprising a vertical main support plate 3402, anupper support plate 3403, and a lower support plate 3405 orientedparallel to the upper support plate 3403. Lower support plate 3405includes a relatively large central opening 3415 for receiving pistonmechanism 3600 therethrough, as further described herein. Upper andlower support plates 3403, 3405 are vertically spaced apart and may behorizontally oriented as shown in the illustrated embodiment, therebydefining a partially or totally enclosed sample processing chamber 3501.Each support plate 3403, 3405 has one peripheral side or end attached tovertical support plate 3402 in a cantilevered manner via a suitablemechanical connection method, such as without limitation welding,soldering, threaded fasteners, adhesives, clips, interlocking features(e.g. tabs/slots), or other and combinations thereof. In one embodiment,support plates 3403 and 3405 may be oriented perpendicularly to the mainsupport plate 3402 as shown.

Centrifuge housing 3401 further includes a safety shield assembly 3404comprising a plurality of shields 3409. The shields enclose the rotarycomponents of the centrifuge 3400 further described herein when spinningat high speeds and thus provide a safety function in the event ofequipment failure. Shields 3409 may include arcuately curved shields,straight shields, or a combination thereof as depicted in theillustrated embodiment in which the front shields are curved. Thestraight shields 3409 may be affixed to housing 3401 byvertically-extending tabs on each top/bottom end which interlock withcomplementary configured slots formed in upper and lower support plates3403, 3405.

Curved shields 3409 may be mounted to the upper and lower support plates3403 and 3405 by pairs of arcuately curved upper shield supports 3407-1,intermediate shield supports 3407-2, and lower shield supports 3407-3.The shield supports may have a semi-circular shape and are verticallyspaced apart as shown. In one embodiment, each shield support includesan inwardly open recess 3410 which receives the shields 3409 and aninwardly curved hook 3411 on each opposing end which traps the shield inthe recess when installed. Shield supports 3407-1, 3407-2, and 3407-3have a complementary radius to the radius of the shields 3409 to providea relatively close and secure mount. A plurality of vertically-extendingstruts 3408 extend between the upper and lower shield supports 3407-1and 3407-3, respectively. The top and bottom ends of each strut 3408 maybe terminated with an elongate tab 3411 received in mating slots 3412 inthe shield supports as best shown in FIG. 51. Other methods of couplingstruts 3408 to the shield supports may be used. The struts 3408 maintainspacing between the upper shield supports 3407-1 and lower shieldsupports 3407-3 and add rigidity to the shield assembly 3404. Shieldsupports 3407-1, 3407-2, and 3407-3 may be welded or soldered to struts3408 to complete the rigid structure.

In one embodiment, the assembly of shield supports 3407-1, 3407-2,3407-3 may be pivotably coupled to housing 3401 via vertically-extendingpivot rods 3414 (see, e.g. FIGS. 43 and 51). This allows the shields3409 to be pivotably opened to access the processing chamber 3501 insidethe housing. Pivot rods 3414 extend through mounting holes 3413 on eachof the opposing sides of support plates 3403, 3405. Mounting holes 3413are positioned near the outboard ends of the supports 3407-1 and 3407-3which are arranged to receive the rods 3414 therethrough. The outboardend portions of shield supports 3403 and 3405 may overlap portions ofthe upper and lower support plates 3403 and 3405 as shown in FIG. 43thereby providing support for the ends of the shield supports.

Although pairs of upper, intermediate, and lower shield supports 3407-1,3407-2, and 3407-3 are disclosed, in other embodiments a single unitaryupper, intermediate, and lower shield support may instead be provided.In other embodiments, the intermediate shield support may be omitted.Other mechanisms or techniques instead of shield supports may be usedfor mounting shields 3409 to the centrifuge housing 3401 may of coursebe used and is not limiting of the invention.

The housing plates 3402, 3403, and 3405, shield supports 3407-1, 3407-2,and 3407-3, and struts 3408 may be formed of any suitable metallic ornon-metallic material in various embodiments. In one non-limitingembodiment, aluminum may be used. Shields 3409 may be metallic,non-metallic, or combinations thereof. In one embodiment, the curvedshields 3409 may be formed of a transparent impact-resistant plasticmaterial to allow operation of the centrifuge to be observed. Straightshields 3409 may be formed of the same material, or metal in someembodiments.

Centrifuge 3400 further includes a motor drive mechanism 3450-1including a vertically oriented and rotatable main drive shaft 3700rotated by a drive mechanism, rotary tube hub 3500 coupled to the driveshaft 3700, and a stationary fluid exchange manifold or dock 3430. Thetube hub 3500 is configured for mounting and supporting a plurality ofsample centrifuge tubes 3450 in a pivotable manner, as further describedherein. The drive mechanism 3450-1 may be raised and lowered by a pistonmechanism 3600 as a unit relative to centrifuge housing 3401 which maybe fixedly attached to a support structure. Each of these components andtheir interaction is described below. As exemplified below, rotary tubehub 3500 is movable between the docked and undocked positions.Alternatively, the fluid exchange manifold or dock 3430 can be driven orboth rotary tube hub 3500 and fluid exchange manifold or dock 3430 canbe driven to dock or undock with each other.

The main drive shaft 3700 of motor drive mechanism 3450-1 is verticallyoriented and defines a rotational axis RA (see, e.g. FIG. 47) creating avertical centerline of centrifuge 3400 for reference purposes. Tube hub3500, fixedly coupled to the lower end of the drive shaft 3700 such asvia tapered coupler 3706 (see, e.g. FIGS. 53 and 71), is rotated or spunby the shaft to process soil samples. In one embodiment, drive mechanism3450-1 may comprise dual motors including a larger main motor 3705 and asmaller indexing motor 3704. The motors are supported by substantiallyplanar upper and lower motor supports 3701, 3702, which may be made ofrectangular metallic or non-metallic plates having a rectangularconfiguration in one embodiment. The motor supports are verticallyspaced apart by a plurality of tubular spacers 3703 in one embodiment tomaintain separation between the motor supports. Each spacer is fixed tothe upper motor support 3701 and slideably connect to the lower motorsupport 3702 via horizontally elongated slots 3710 (see, e.g. FIG. 76).The upper motor support is thus slideably movable relative to the lowermotor support. Four spacers 3703 may be provided in one embodiment witha spacer located near each of the four corners of the motor supports3701, 3702. It bears noting that motor supports 3701, 3702 are freefloating and not fixedly attached to centrifuge housing 3401 to allowthe drive mechanism to be raised and lowered via operation of pistonmechanism 3600, as further described herein.

Main motor 3705 includes an associated main gear 3707 driven by themotor shaft of the main motor. Indexing motor 3704 similarly includes anassociated indexing gear 3708 driven by the motor shaft of the indexingmotor. Both gears 3707 and 3708 are selectively engageable with the maindrive pulley gear 3709 which is fixedly attached to the top end of maindrive shaft 3700 such as via set screws or other means. A toothed timingbelt 3713 shown in FIG. 95 winds around and operably interconnects allthree gears to provide a belt-drive system for rotating the main driveshaft 3700.

To adjust tension in the timing belt 3713, the upper motor support 3701is slid in one of two opposing direction toward or away from the maindrive shaft 3700, which is fixed in horizontal position in the lowermotor support 3702 via a mounting hole. The main and indexing motors3705, 3704 are fixed in horizontal position to the upper motor support3701 via respective mounting holes. Sliding the upper motor support 3701relative to the lower motor support 3702 back and forth allows the userto properly obtain the proper tension in the belt. The spacers 3703 willslide in their respective slots 3710 in the lower motor support whenadjusting the belt tension.

The main motor 3705 is used to rotate the rotary tube hub 3500 atrelatively high speeds for centrifugating the soil samples. The indexingmotor 3704 is used to properly align and index the tube hub inrotational position relative to the fluid exchange dock 3430 forexchanging fluids between the centrifuge tubes 3450 carried by the huband the dock. In one embodiment, indexing motor 3704 may be a steppermotor whose output is used to engage and incrementally rotate the maindrive shaft 3700 in very small discrete steps to achieve properrotational alignment between the dock and tube hub. This allows veryprecise speed control and positioning (i.e. motion control) of the maindrive shaft which can be controlled by the system programmablecontroller. The stepper motor functions in cooperation with indexingfeatures on the tube hub 3500 and centrifuge housing 3401 to achieveproper rotational alignment between the dock 3430 and tube hub 3500 whenthe hub is in a docked position. This ensures that the clusters 3433 offlow passages 3434 in the fluid exchange dock 3430 are concentricallyaligned with flow ports 3451 formed in the top surface of centrifugetubes 3450 for exchanging fluids when the tube hub 3500 is in the upperdocked position. In one embodiment, a rotational sensor (not shown) suchas a Hall effect sensor may be provided which detects and communicatesthe rotational position of main drive shaft to the system controller,which in turn may control operation of the stepper motor and therotational position of main drive shaft 3700.

Referring to FIGS. 43-56, dock 3430 includes a generally disk-shapedannular body having a central opening 3435, which may be coaxiallyaligned with rotational axis RA for passage of drive shaft 3700therethrough. Dock 3430 is fixedly attached to upper support plate 3403,such as via threaded fasteners or other means and remains stationarywith housing 3401. The dock body may have a generally solid metallic ornon-metallic structure in one embodiment. In one embodiment, dock 3430may be formed of plastic. A plurality of flow holes or passages 3434extend vertically through the body between and through top and bottomsurfaces 3431, 3432 of the fluid exchange dock 3430. The flow passages3434 may be arranged in clusters 3433 having a number and pattern whichmatches and coincides with the number of centrifuge tubes 3450 andclusters 3451 of flow ports formed in the top surface of the tubes. Whenthe centrifuge tubes 3450 are selectively mated to and engaged with thedock 3430, the flow ports 3451 and flow passages 3434 are concentricallyaligned and in fluid communication. This allows sample slurry to beinjected into and extracted from the centrifuge tubes 3450. In oneconfiguration, clusters of three flow passages 3434 and conduits 3451may be provided. Other embodiments may have more or less holes/conduitsin each cluster.

The lower ends of each flow passages 3434 in dock 3430 may be terminatedin a nozzle 3436 which is at least partially insertable into the openflow ports 3451 for forming a fluidic sealed connection therebetween(see, e.g. FIG. 56). Nozzles 3436 may be disposed inside downwardly openholes formed in the bottom surface 3432 of dock 3430 in one embodiment,thereby forming pin-like projections extending downwards from the dock.

Referring now to FIGS. 43-52 and 57-58, rotary tube hub 3500 has agenerally disk-shaped body including a central opening 3515 coaxiallyaligned with rotational axis RA for passage of drive shaft 3700therethrough. A tapered coupler 3706 is affixed to the bottom end ofdrive shaft 3700 which secures the tube hub 3500 to the drive shaft.Bushing 3508 may be secured in turn to the drive shaft 3700 via athreaded fastener (not shown) in one example.

Rotary tube hub 3500 is configured for pivotably mounting centrifugetubes 3450 to the hub for centrifuging the tubes with sample slurrytherein. The hub 3500 includes a top surface 3510, opposing bottomsurface 3511, and a circumferentially-extending peripheral sidewall 3512extending between the surfaces (best shown in FIG. 57). Rotary hub 3500includes a plurality of radially and outwardly open peripheral recesses3502 formed through the sidewall 3512; one recess for each centrifugetube 3450. Recesses 3502 are further upwardly and downwardly open. Thisallows the centrifuge tubes 3450 to pivot radially outwards and upwardsas the centrifuge is rotated to high speeds. The peripheral recesses3502 may have a generally rectilinear shape in one embodiment and may bearranged in diametrically opposed pairs. In one construction, eightrecesses may be provided; however, more or less recesses may be provideddepending on the number of centrifuge tubes used and soil nutrients tobe analyzed.

With additional reference to FIGS. 59-65, centrifuge tubes 3450 may eachbe pivotably mounted in a respective peripheral recess 3502 by a pivotpin 3459 (shown in FIGS. 57 and 59). The opposing ends of pivot pin 3459are received in upwardly open pin slots 3503 formed on each side of therecess 3502 which also open inwardly towards the recess (see, e.g. FIG.57). Slots 3503 have a depth that extends only partially through thethickness of the dock 3500 (measured between the top and bottom surfaces3510 and 3511) so that the slot does not penetrate the bottom surface.This forms a seating surface which can engage the pivot pin 3459. Pivotpins 3459 are inserted through a transversely oriented through-hole 3454formed through centrifuge tube 3450 such that the ends of the pin remainexposed. Pivot pins 3459 thus preferably have a greater length than thetransverse width of the centrifuge tubes measured in the direction ofthe through-hole 3454 for this purpose. When mounted, the pins 3459bridge across the recesses 3502 within each tube 3450.

To lock and trap the exposed ends of the pivot pins in slots 3503,locking caps 3505 are provided in one embodiment as best shown in FIGS.64 and 65. To mount each centrifuge tube 3450 to the tube hub 3500, oneof the pivot pins 3459 is first inserted through the through-hole 3454so that each end of the pin remains exposed. The tube 3450 is insertedinto the peripheral recess 3502 with the pin 3459 positioned above thepin slots 3503 straddling the recess. The centrifuge tube 3450 islowered downwards in the recess 3502 until the pivot pin 3459 ends enterand are fully seated inside the pair of pin slots 3503. One of thelocking caps 3505 is then engaged with each of the slots 3503 to lockthe pin in the slots. The locking caps 3505 may be configured to form asnap fit with the slots 3503 in one embodiment. In other embodiments,the locking caps 3505 may be retained in position on the pin slots 3503by an aerodynamic cover assembly instead of or in addition to the snaplock fit.

The prime purpose of the aerodynamic cover assembly is to streamline thetube hub 3500 assembly as it spins to reduce power input and noise dueto aerodynamic losses since the tube hub with centrifuge tubes would actas an air impeller otherwise. The cover assembly comprises an uppercover 3520 and lower cover 3521 which are affixed to the hub such as viathreaded fasteners in one embodiment or other mechanical fasteningmethods. FIGS. 51-54 show the covers. The hub 3500 is thus sandwichedand compressed between the covers, as further shown in FIGS. 66 and 67which depict the completed hub assembly. The cover assemblyadvantageously also serves to trap the locking caps 3505 beneath theupper cover 3520 as noted.

With continuing reference to FIGS. 51-54 and 66-67, each of the upperand lower covers 3520, 3521 may have a disk-shaped body including acentral opening 3522 and plurality of rectangular tube openings 3523formed completely through the cover between their top and bottomsurfaces. Tube openings 3523 may be arranged in a circumferentialpattern around central opening and are radially elongated as shown. Thetube openings 3523 are arranged to coincide with the layout andarrangement of the peripheral recesses 3502 formed in hub 3500 such thatthe mounted centrifuge tubes 3450 are exposed within the covers (see,e.g. FIGS. 66-67). Tube openings 3523 preferably have a radial lengthsized to allow the mounted centrifuge tube to fully swing outwards andupwards within the opening when rotated by the centrifuge 3400 (see FIG.67). Centrifuge tubes 3452 are each angularly movable between a verticalposition shown in FIG. 66 when the rotary tube hub 3500 is stationary,and a horizontal position shown in FIG. 67 when the hub is rotated atfull speed by the drive mechanism. This ensures that the accelerationexperienced by the sample due to gravity or rotational acceleration isalways away from the tube ports. The tubes 3450 are preferablyconfigured with the through-hole 3454 located more proximately to thetop surface 3452 of the tube such that the top surface is substantiallyflush with the top surface 3524 of the upper cover 3520, or preferablyslightly raised and protruding above the top surface as seen in FIG. 66to be engaged by the bottom surface 3432 of the dock 3430 to form asealed connection between the flow ports 3451 of the tube and flowpassages 3434 of the dock 3500 as previously described herein. In thevertical position, the centrifuge tubes 3450 project downwards below thebottom surface 3525 of the lower cover 3521 such that a majority of theheight of the tube extends beneath the bottom surface 3525 (see, e.g.FIGS. 53-54).

To ensure proper angular alignment between the clusters of flow ports3451 of the centrifuge tubes 3450 and flow passages 3434 of the fluidexchange dock 3500, centrifuge 3400 further includes an indexingmechanism comprising mating index features disposed in/on the rotarytube hub 3500 and centrifuge housing 3401. In one embodiment, the indexfeatures on tube hub 3500 comprise a plurality of circumferentiallyspaced apart and upwardly open index depressions 3530 formed on thehub's top surface 3510 encircling central opening 3515 (see, e.g. FIG.57). Depressions 3530 mate with a plurality of complementary configuredand downwardly protruding index protrusions 3531 disposed in centrifugehousing 3401, which are arranged in the same circumferential pattern asthe index depressions. In one embodiment, index protrusions 3531 may beformed on an annular shaped index ring 3533 fixedly attached to thebottom surface 3432 of fluid exchange dock 3430 by any suitable means(see, e.g. FIG. 68). Ring 3533 with index protrusions 3531 representsthe fixed component of the indexing system whereas the rotary tube hub3500 with index depressions 3530 is the movable component. In otherembodiments, the index depressions 3530 may be on the ring 3533 andprotrusions 3531 located on hub instead. Ring 3533 further includes acentral opening 3534 for passage of main drive shaft 3700 and pistonsupport tube 3604 therethrough. The foregoing mating indexing featuresare used in conjunction with the indexing motor 3704 to achieverotational alignment between the index depressions and protrusions,thereby allowing insertion of the protrusions into the depressions whenthe rotary tube hub 3500 is in the upper docked position.

Reference is made now to FIGS. 59-63 and a vertical orientation ofcentrifuge tubes 3450 in these figures for convenience of description,recognizing that the tube changes between the vertical and horizontalpositions previously described herein when pivotably rotated bycentrifugal forces when the centrifuge is operated. The centrifuge tubes3450 generally function to separate a clear supernatant from the soilsample slurry and extractant mixture for chemical analysis. Centrifugetubes 3450 may each have a rectangular cuboid body in one non-limitingembodiment including top surface 3452, opposing bottom surface 3453, andfour lateral sides 3458 extending vertically between the top and bottomsurfaces. The body of each tube 3450 may be completely or partiallysolid in construction. In one embodiment, centrifuge tubes 3450 may beformed of injection molded plastic. Top surface 3452 is penetrated byflow ports 3451 for introducing the slurry-extractant mixture andextracting the clear supernatant after centrifugating theslurry-extractant mixture. The ports include a slurry port 3455-1,supernatant extraction port 3457-1, and cleanout port 3456-1. Each portfluidly connects to its respective fluid conduit 3455-2, 3456-2, and3457-2 which extend vertically downwards from the ports inside tube3450. Slurry and cleanout conduits 3455-2 and 3456-2 respectively may bevertically oriented and are fluidly connected via a cross flow conduit3460 (see, e.g. FIG. 61). Supernatant extracting conduit 3457-2 isobliquely angled to centerline CT of centrifuge tube 3450 and fluidconduits 3455-2 and 3456-2. Conduit 3457-2 is fluidly connected toslurry conduit 3455-2 (see, e.g. FIG. 63). None of the conduitspenetrate the bottom surface 3453 of tube 3450. In some embodiments, theslurry conduit 3455-2, cleanout conduit 3456-2, and supernatantextracting conduit 3457-2 may have a high length to diameter ratio (L/D)to create high velocity flow during the centrifuge tube 3450 waterflushing and cleaning procedure to thoroughly clean the tubes. In someembodiments, each conduit may have an L/D greater than 10.

According to another aspect, the centrifuge 3400 includes a pistonmechanism 3600 operable to raise and lower the motor drive mechanism3450-1 and rotary tube hub 3500 operably coupled thereto relative to thestationary housing 3401. Referring initially to FIGS. 70 and 71, pistonmechanism 3600 includes a cylinder 3601 defining an internal chamber3603, a piston 3605 comprising an annular piston ring 3602, and anelongated drive support tube 3604 extending through the sleeve andchamber 3603. A return spring 3607 inside cylinder 3601 biases pistonring downwards. Motor drive shaft 3700 extends vertically throughsupport tube 3604 and is rotatable relative to the tube which does notrotate via operation of the motor drive mechanism 3450-1. Axially spacedapart annular bearings 3608 support the drive shaft 3700 at each end ofthe tube for rotational movement (FIG. 71). The support tube 3604 andbottom of piston cylinder 3601 are fluidly sealed to the fluid exchangedock 3430 by an annular seal 3609 (see, e.g. FIG. 72) which isconfigured to allow the tube to slide up or down through the dock.

Cylinder 3601 is fixedly attached to housing 3401 via cylinder supportmember 3406 (see, e.g. FIGS. 53-54) and thus remains stationary duringoperation of the piston. Support member 3406 may have a plate-like bodyand be affixed to housing main support plate 3402 via interlocking tabsand slots. Other modes of attaching support member 3406 to plate 3402may be used including welding or fasteners as examples. In oneembodiment, cylinder 3601 may be coupled to support member 3406 viathreaded fasteners.

With additional general reference to FIGS. 43-54 and FIGS. 70-71, piston3605 is slideably disposed inside the internal cylinder chamber 3603 forupwards/downwards movement therein. Piston head 3602 is provided withannular seals (e.g. O-rings) on both the inside and outsidecircumferential surfaces of the head. This forms leak resistant fluidseals between the head 3602 and the support tube 3604 and cylinder 3601within chamber 3603 to maintain air or hydraulic fluid therein used tooperate the piston.

Piston head 3602 is fixedly attached to support tube 3604 at a positionbetween the ends of the tube. The top end of support tube 3604 is inturn fixedly attached to the lower motor support 3702. Accordingly,moving piston 3605 upwards and downwards in piston cylinder 3601therefore moves the support tube 3604 with the motor drive and tube hubattached thereto upwards/downwards when the piston is actuated (compareFIGS. 72 and 73). This axially moves the tube hub 3500 between its upperdocked and lower undocked positions for exchanging fluids with thecentrifuge tubes 3450 (e.g. slurry-extractant, supernatant, or tubeflushing water-air stream) in the upper position, or alternativelycentrifugating the soil samples in the tubes in the lower position.

Operation of the piston mechanism 3600 will now be briefly describedwith reference to FIGS. 72-73. In one embodiment, piston 3605 may be airoperated and fluidly connected to a source of operating air such as airtank 3031 (see, e.g. FIG. 1 air lines to centrifuge). In one embodiment,an air conduit 3714 formed in the fluid exchange dock 3430 (see, e.g.FIG. 55) is provided to introduce operating air into chamber 3603 ofcylinder 3601. This allows operating air to be introduced into orremoved from the cylinder chamber 3603 for raising or lowering thepiston 3605 and support tube 3604 assembly (along with motor drive androtary tube hub 3500 coupled thereto) which collectively form a movableunit actuated by the piston. Tube hub 3500 is normally in the defaultlower position when operating air is not supplied to piston cylinder3601 as seen in FIG. 73. Tube hub 3500 is disengaged and spacedvertically apart form fluid exchange dock 3430 being in an “undocked”position. To “dock” the tube hub 3500 with dock 3430, air is supplied tochamber 3603 of cylinder 3601 beneath the piston head 3605. This raisesthe piston head 3605, which in turn raises the tube hub 3500 to itsupper position via support tube 3604 and the motor drive mechanism3450-1 as seen in FIG. 72 until the hub engages the dock 3430. To returnthe rotary tube hub 3500 to the lower position, air is simply releasedfrom the cylinder 3601 such as via a three-way air valve similar tothose already described herein in relation to the mixers. Piston returnspring 3607 automatically returns the piston, drive mechanism, and tubehub downwards. The centrifuge 3400 is now ready to rotate the tube hub3400 and centrifugate the soil slurry samples as seen in FIGS. 74 and 75with hub in the lower position.

The chemical analysis sub-system 3003 further includes an absorbanceanalysis cell 3800 for performing colorimetric analysis of thesupernatant after addition of a color-changing chemical reagent.Analysis cells of some sort are commonly used in absorbance measurementsystems, but not embodiments such as those disclosed herein. Referringto FIG. 77, the cell 3800 may comprise a generally rectangular cuboidbody 3801 which may be molded of a transparent or translucent plasticmaterial. A pair of diagonally opposing top and bottom corners may beangled at a diagonal and define a threaded inlet and outlet ports 3802and 3803 as shown. Inlet port 3802 is fluidly coupled to mixing coil3318 which receives an influent from supernatant pump 3312 and reagentpump 3316 (see, e.g. FIG. 1). Outlet port 3803 discharges the effluentto waste/exhaust. The inlet and outlet ports 3802 and 3803 may fluidlycoupled to flow tubing 3021 via threaded tube connectors. The inlet andoutlet ports are fluidly coupled together by a Z-shaped internal flowconduit 3804 in cell 3800 comprising two obliquely angled diagonalsections extending diagonally and a horizontal straight sectiontherebetween. A threaded LED emitting port 3805 and receiving port 3806are each disposed on opposite lateral sides of the cell body at the endsof the straight horizontal section of flow conduit 3804 as shown. Ports3805 and 3806 are linearly aligned. Emitting port 3805 is coupled to anemitting diode circuit board 3807 including an LED emitting diode.Receiving port 3806 is coupled to a receiving diode circuit board 3808including an LED receiving diode. In operation, supernatant extractedfrom the centrifuge tubes 3450 to which a reagent is added and mixed isreceived at the inlet port 3802 (see directional flow arrows). Themixture flows upwards through the first diagonal section of flow conduit3804 to the straight section of the conduit at the emitting diode portend. The mixture then horizontal transverses the straight section in alinear flow path aligned with both the emitting and receiving diodes tothe second diagonal section of the flow conduit at the receiving diodeport end. Colorimetric analysis of the sample is performed by the systemwithin the horizontal straight section of the flow conduit 3804 toquantify the nutrient or analyte being analyzed in the soil sample atthis time. The supernatant and reagent mixture then flows upwardsthrough the second diagonal section of the flow conduit and isdischarged from the outlet port 3803. Advantageously, mixture flowsinline and parallel with the direction of light emitted by the emittingdiode in the straight section of the flow conduit 3804 as shown. Thisincreases and maximizes the time for colorimetric analysis of thesample, thereby improving accuracy yet quickly processing the sample.

In one embodiment, a plurality of analysis cells 3800 may be provided toallow multiple samples to be processed simultaneously in parallel fordifferent nutrients or analytes, thereby decreasing the time required tofully analyze a given soil sample for levels of multiple nutrients oranalytes.

FIGS. 78-94 are schematic flow diagrams showing chemical processingtrain 3000A of the chemical analysis sub-system 3003 of FIG. 1 depictingsequential views of a method or process for processing and analyzing asoil sample. These diagrams therefore represent the processing sequencewhich occurs in a single chemical processing train 3000A of FIG. 1. Itwill be appreciated that in some implementations of the method, the samesequential process shown is performed simultaneously in parallel in allof the processing trains of the soil sampling system 3000 to analyze thesoil sample slurry for all chemical parameters of interest (analytes),thereby resulting in a significant reduction in sample processing time.Each processing train may therefore process and analyze the sample for adifferent analyte to complete the full chemical analysis profile of thesoil sample.

The process described below and in the flow diagrams may beautomatically controlled and executed by the system programmablecontroller, such as for example processing system 2820 disclosed incopending U.S. patent application Ser. No. 15/806,014 filed Nov. 7,2017. The controller is operably coupled to the components shown inFIGS. 78-94 (e.g. pumps, valves, centrifuge, compressor, etc.) forcontrolling the process sequence and flow of fluids through the systemto fully process and analyze the soil sample.

In the flow diagrams, it bears noting that the emboldened and thickerdark lines represent the active fluid flow paths during each of theprocess sequences shown and described. Valve position of thepneumatically or electrically actuated fluid valves 3331 and air valves155 a, 167 are schematically represented by solid or open circles (solidcircle=closed; open circle=open). Attention is drawn to the open andclosed valves in the flow diagrams which create the active portions ofthe flow network. Valves 3331 may be pneumatically operated pinch valvesin one non-limiting example.

FIG. 78 shows the provision of the soil sampling system 3000 at thestart and readied for processing and chemically analyzing a soil sample.In FIG. 78, after collection of the “dry” sample soil “cores” directlyfrom the agricultural field by a sample collector (e.g., collectionprobe) 3033 of the probe collection sub-system 3001, the cores arepneumatically transferred (i.e. blown) via process tubing 3021 ofsuitable size to the sample collection/volumizing station 160-1 disposedabove mixer 100 or 200 (previously described herein) by delivering apulse of air via air valve 3032. The sample cores from multiple samplinglocations (i.e. different depths and/or areas) collected by the soilcollection probe 3033 may be aggregated together in thecollection/volumizing station to create a combined “sample.” Pressurizedair provided via air valve 3032 provides the motive force fortransferring the soil core to station 160-1. In FIG. 79, this aggregated“sample” is then volumized in the manner previously described herein(i.e. mass is estimated to determine proper amount of water to add tothe mixing chamber of the mixer to form a soil sample slurry of properviscosity/consistency).

In FIG. 80, the aggregated sample is transferred (e.g. dropped into) tothe mixing station (e.g. mixer-filter apparatus 100 or 200). In FIG. 81,water has been added to the sample via water pump 3304 in apredetermined water/soil ratio and mixed to form a soil sample slurry.All valving connected to the mixer is closed as shown during the mixingoperation. In FIG. 82, slurry pump 3333 draws a known ratio of slurryand pumped extractant into the mixing loop or coil 3330 and past thesecond open valve 3331 to exhaust/waste to establish stable flow beforethe next stages in sample processing occurs. The extractant pump 3310rate compared to the slurry pump rate determines the slurry toextractant ratio. For example, if slurry pump draws total flow of 4mL/sec, and extractant pump runs at 1 mL/sec, then the ratio will be 3:1(Total rate (sample pump) minus extractant rate=raw slurry rate). Notethe open position of the two slurry pump isolation valves 3331.

In FIG. 83, at this point in the process, there is a stagnant fluidpocket (represented by a dashed line) in tubing 3021 between the twojunctions on either side of the stagnant fluid pocket that has not beenfilled yet with soil sample slurry. The pocket may contain air and/orliquid. To remedy this situation, the two previously open slurry pumpisolation valves 3331 upstream and downstream of slurry pump 3333 areclosed and the flow conduits are changed from the once-throughload/unload configuration to a recirculation closed pump loopconfiguration which includes the stagnant section of tubing 3021 andmixing loop or coil 3330. Slurry pump 3333 pumps slurry fluid backwardsa small amount through the closed pump loop to relocate the stagnantfluid pocket into position so it can be exhausted in the following stepsand fills the previously empty and stagnant tubing section with slurryas shown in FIG. 84.

In FIG. 85, the flow conduits are reconfigured again by opening theslurry pump isolation valves 3331 to change the conduits from the closedpump loop configuration back to load/unload configuration. More sampleslurry and extractant are pumped by slurry pump 3333 through the tubing3021 to purge the stagnant pocket to exhaust.

In FIG. 86, at this point in the process, the entire slurry loop(represented by dashed lines) is full of slurry and extractant in aprecisely known ratio. In FIG. 87, slurry pump 3333 can be operated tomix in the closed pump loop shown if necessary to speed up extraction ofthe analyte from the slurry. The closed pump loop is forming by closingthe two slurry pump isolation valves 3331 and opening the intermediatevalve between the pump inlet and the mixing coil 3330 as shown. In FIG.88, the now thoroughly mixed soil sample slurry is ready to be pumped tothe centrifuge to separate the liquid from the soil particles in theslurry which produces the clear supernatant for colorimetric analysis.The valves 3331 are changed in position as shown (i.e. open/closed) toreconfigure the flow conduit configuration again from the recirculationclosed pump loop configuration to once-through load/unloadconfiguration. Previously closed cleaning valve 3331 fluidly coupled towater pump 3304 and the air vent valve 3331 fluidly coupled to air vent3306 are opened as shown to allow a cleaning air/water mixture to bedrawn into the slurry flow tubing by slurry pump 3333 in order to flushthe tubing out. Entrainment of air bubbles in the aerated water improvesthe effectiveness of cleaning the tubing. This step also pushes thesample slurry to the centrifuge 3400, and into and through centrifugetube 3450 which then flows to exhaust/waste. Slurry pump is operated 2×the rate as water pump 3304 in order to draw air bubbles into tubingconduits for more effective cleaning later.

In FIG. 89, centrifuge 3400 undocks from fluid exchange dock 3430, andcentrifugates the slurry sample in the manner previously describedherein to create the transparent supernatant containing the analyte(i.e. chemical constituent of interest). In FIG. 90, centrifuge 3400re-docks, then supernatant pump 3312 draws or pulls a small amount ofsupernatant from centrifuge tube 3450 through fluid exchange dock 3430and past the reagent injection junction in the tubing 3021 as shown.This column of supernatant contains: (1) any debris that was in theconnection point, and (2) a raw sample of supernatant to use as a “zeropoint” for absorbance before the reagent indicator is added. The slurryport 3455-1 in centrifuge tube 3450 (see, e.g. FIG. 59 et seq.) is usedas a vent to atmosphere so air can replace supernatant in the centrifugetube as the supernatant is drawn out by supernatant pump 3312 to preventforming a vacuum which would impede the removal of supernatant from thecentrifuge tube.

In FIG. 91, reagent pump 3316 and supernatant pump 3312 operate atdesired ratio to pump the mixture through the mixing coil 3318 andthrough the flow cell 3800 to exhaust/waste. The initial (potentiallydirty) sample is ignored, then the middle portion of the sample is usedas the control, and the final portion is the portion that indicates thedesired value representative of the initial soil sample.

The flow conduits are next cleaned and flushed for processing the nextsample. In FIG. 92, the water/air mixture pumps via slurry pump 3333through the slurry loop portion of the flow conduits to clean slurryloop. The centrifuge 3400 is fluidly isolated from the slurry loop asshown (note valving positions). In FIG. 93, the water/air mixture pumpsto centrifuge 3400 and through the centrifuge tube 3450 for cleaning.Note that the air vent 3306 is open and active to draw and entrainambient air into the form of bubbles into the water which acts to scrubthe exposed surfaces in the components to be cleaned. Alternatively orin addition, chemicals, and/or abrasive particles may be introduced intothe cleaning water stream to further facilitate more aggressive cleaningmeasures if required. In FIG. 94, high pressure air from compressor 3030is used to aggressively push the water/air mixture through centrifugetube for final cleaning. The system is now prepared to process the nextsample in a similar manner to that described above.

It will be appreciated that variations and different ordering of theforegoing process steps for chemically processing a soil sample may beused in other embodiments. The process is therefore not limited tonumber and types of operations presented herein, which represent onepossible and non-limiting operating scenario.

Alternative Supernatant Separators

In some alternative embodiments, liquid may be separated from the soilsample to produce clear supernatant for chemical analysis using suitablefilter media in lieu of the centrifuge 3400 and its centrifuge tubes3450 described elsewhere herein.

FIG. 261 is a flow chart showing the same centrifuge-based soil sampleprocessing and analysis system of FIGS. 78-94, but with the centrifuge3400 replaced by a suitable micro-porous filter 5757 configured andconstructed to produce the clear supernatant from the soil slurry andextractant mixture. The slurry/extractant mixture is pumped underrelatively high pressure by slurry pump 333 in a flow path establishedvia flow tubing 3021 and select opening/closing certain valves 3331through the preferably back-washable porous filter 5757. The filter 5757is configured and constructed to withstand the high pressure. The filteris shown schematically. In operation, the supernatant exits the filter5757 and flows to supernatant pump 3312, and then is pumped through theremainder of the sample analysis loop where the supernatant is mixedwith reagent and analyzed in the same manner already previouslydescribed herein and shown in FIGS. 78-94.

Once the supernatant is separated from the soil slurry, the filter maybe back-flushed with clean high pressure liquid (e.g. filtered water)using water pump 3304 to clean the filter media for reuse during thenext soil sample run. To accomplish a backwash cycle, the flow pathsformed by flow tubing 3021 in the system may be reconfigured byselectively opening/closing certain valves 3331 in combination toreverse filtered water flow through the filter media of filter 5757.Additional filter backwash flow tubing 3021-1 and valving 3331 may beprovided as shown in FIG. 261 to reverse the flow. The filter backwashis exhausted from the system.

In some embodiments, a porous sintered metal filter media of suitableshape and structure may be used for filter 5757. FIG. 262 shows onenon-limiting example of an inline type filter 5757 with tubularcylindrical shaped metal filter media encased in a complementaryconfigured housing 5757-1 which includes an inlet fitting 5757-2 andoutlet fitting 5757 each configured for connection to external flowtubing or piping (e.g. threaded or tubing connector). Of course,numerous other suitable types and configurations of filters may be usedto suit the apparatus used to mount and retain the filter (e.g. diskshaped, cone shaped, solid cylinder shape, etc.). Other types of porousfilter media may be used which are suitable for pressure requirements ofthe system (e.g. polymeric, etc.). Preferably, the filter media materialand shape selected are suitable for backwashing.

FIG. 263 is a flow chart showing the same centrifuge-based soil sampleprocessing and analysis system of FIGS. 104-119 described elsewhereherein comprising a microfluidic processing or disk 4000 in a carouselassembly with analysis processing manifolds (e.g., wedges) 4002, butwith the centrifuge 3400 replaced by a suitable micro-porous filter 5757in the process to produce the clear supernatant from the soil slurry andextractant mixture. In this case, filter 5757 may be configured andconstructed for mounting onboard within each of the processing wedges4002 as shown (dashed lines connoting the boundary of the wedge). Thefilter operates in the same manner and flow sequence already describedelsewhere herein with respect to use of the centrifuge instead. Asuitable external off-disk high pressure filtered water source may beused for the filter backwash operation, which is conducted in a similarmanner to that already described herein by reversing flow through thefilter media.

Chemical Analysis Sub-System Alternative Embodiment

FIGS. 96-136 generally depict various aspects of an alternativeembodiment of chemical analysis sub-system 3003 based on centrifuge 3400previously described herein. In this embodiment, however, a microfluidicprocessing disk 4000 is added which mounts above and is in fluidcommunication with the fluid exchange dock 3430 which is detachablyfluidly coupled to centrifuge tubes 3450 carried by hub 3500.Advantageously, the microfluidic processing disk 4000 is a microfluidicdevice (e.g. M2D2) which is configured and operable to integrate andincorporate the entire slurry analysis system including substantiallyall aspects of fluid pumping, mixing, valving, and flow distribution andcontrol previously shown in FIG. 1 associated with handling the slurry,extractant, reagent, and supernatant fluids. The pumps, valving, mixing,and flow distribution functions for example are thus integrated intomicrofluidic processing disk 4000 in a known manner of constructingmicrofluidic devices with active micro-components (e.g. pumps, valves,mixing chambers, etc.). This eliminates the need for the multiplicity ofphysically discrete and separate flow control devices (e.g. pumps,valves, mixing chambers, etc.) which need to be fluidly interconnectedvia tubing, thereby allowing for improved compactness of the centrifuge3400 and its ancillary components associated with the chemicalprocessing and analysis portion of the system. The microfluidicprocessing disk 4000 advantageously provides single unified platform ordevice for processing and controlling flow of all the foregoing fluidsin addition to chemical analysis and quantification of the analytes ofinterest extracted from the soil sample. The microfluidic processingdisk 4000 further provides parallelization of the soil sample processingto reduce analysis time and quantification of all chemical parametersassociated with the sample. Pressurized air provided by air compressor3000 (shown in FIG. 1) or another compressor provides the motive forcefor flowing and processing the foregoing fluids through the microfluidicprocessing disk 4000 in accordance with the flow charts of FIGS.104-119, as further described herein.

Referring initially to FIGS. 96-103, the microfluidic processing disk4000 may have a generally disk-shaped composite body in one embodimentformed from multiple layers of material bonded or laminated together byany suitable means used in the art (e.g. adhesives, heat fusion, etc.).Each layer may be substantially planar or flat in the sandwichedconstruction, typical of microfluidic devices (e.g. M2D2). One or moreof the layers are configured and patterned to create micro-sizedchannels, chambers/reservoirs, and diaphragm-operated valves and pumpsembedded in the microfluidic devices in a known manner. The materialsused to construct the layers of the microfluidic processing disk 4000may include a combination of rigid thermoplastics and flexibleelastomeric material sheets. Transparent materials may be used in oneembodiment to permit visual observation of the fluids being processed inthe microfluidic processing disk 4000. The rigid plastics may be used toform the overall rigid substrate or body of microfluidic processing disk4000 which defines its exposed exterior surfaces and includes aninterior patterned to create a plurality of internal microchannels 4012and chambers for creating the active microfluidic flow control devices(e.g. diaphragm-operated pumps, valves, mixing chambers, etc.). Examplesof thermoplastics which may be used include for example withoutlimitation PMMA (polymethyl methacrylate commonly known as acrylic), PC(polycarbonate), PS (polystyrene), and others. Examples of suitableelastomeric materials which may used include for example withoutlimitation silicone, PDMS (polydimethylsiloxane), neoprene, and others.The elastomeric materials may be used to form the flexible anddeformable active portions of the microfluidic flow control devices suchas the movable diaphragms of the micropumps and microvalves which areacted upon by air pressure (alternatively water pressure) to operatethese pumps and valves for controlling fluid flow within themicrofluidic processing disk 4000. This is typically achieved by forminga thin flexible elastomeric layer (e.g. silicon, PDMS, etc.) above alayer of the more rigid thermoplastic layer in disk 4000 which ispatterned with the microchannels and microchambers associated with thepumps, valves, or mixing chambers, thereby forming a flexible roofportion thereof. Applying air pressure to the top of the normally flatelastomeric deforms and deflects the elastomeric material downwards toseal off and close the microchannel/microchamber. Removing air pressurecauses the elastomeric material to return its original flat conditionvia its elastic memory to reopen the microchannel/microchamber. Thistype action is well known in the art without undue further elaboration.In some embodiments, a vacuum may optionally be applied to return theelastomeric material to its original condition if removal of airpressure alone does not suffice.

In one embodiment, the disk-shaped microfluidic processing disk 4000comprises a plurality of generally interchangeable and separabletriangular or “pie-shaped” chemical processing wedges 4002. The wedges4002 may be detachably interlocked together such as via suitablemechanical interlock features (e.g. snap-fit tabs/slots, etc.) and/orfasteners to collectively form the body of the processing disk 4000. Inother embodiments, the wedges 4002 may be permanently joined togethersuch as via adhesives or ultrasonic welding as some examples

Each processing wedge 4002 of microfluidic processing disk 4000 is adiscrete microfluidic device which may be fluidly isolated from everyother processing wedge in one embodiment within the confines of theprocessing disk structure (i.e. no cross flow through the disk). Beyondthe microfluidic processing disk physical boundary, however, individualprocessing wedges may fluidly share common inlet manifolds connected toa source flow (e.g. water, slurry, air) or outlet manifolds (e.g.waste/exhaust manifold) for convenience of construction. Each processingwedge 4002 is a complete chemical processing device or train operable toprocess and analyze a soil sample initially provided in slurry form(from one of the mixing stations previously described herein) for adifferent analyte. Advantageously, this provides a plurality of chemicalprocessing trains (i.e. wedges 4002) capable of processing and analyzingsoil samples simultaneously in parallel for different analytes (e.g.plant-available nutrients or other chemical constituents/properties) inconjunction with the centrifuge 3400. This parallelization reduces thetime required for completely processing and analyzing a soil sample formultiple analytes. Microfluidic processing disk 4000 is configured andoperable to form a detachable fluid coupling to centrifuge tubes 3350carried by the rotary tube hub 3500 through intermediary fluid exchangedock 3430 previously described herein. Fluid exchange dock 3430 isfluidly coupled and interposed between the microfluidic processing disk4000 and centrifuge tubes 3350.

Each processing wedge 4002 may have a truncated wedge shape including atop major surface 4003, an opposing bottom major surface 4004, opposingarcuately curved inner and outer surfaces 4005, 4006, and a pair ofconverging radial side surfaces 4007. Side surfaces 4007 each defineradial reference lines R1 which intersect at a geometric verticalcenterline C1 of the processing wedge 4002. When the processing wedges4002 are assembled together in microfluidic processing disk 4000, theycollectively define a circular central opening 4014 (for purposessimilar to central opening 3435 of dock 3430). Processing wedge 4002defines an outer peripheral portion or region 4008 defined as proximateto outer surface 4006, and an inner hub portion or region 4009 definedas proximate to inner surface 4005. Although the non-limitingillustrated embodiment includes eight processing wedges 4002, otherembodiments may use more or less wedges.

A plurality of fluid exchange ports are formed in each processing wedge4002. The ports may include a plurality of outer ports 4010 arranged inan array in peripheral region 4008 of the processing wedge, and aplurality of inner ports 4011 arranged in an array in the inner hubregion 4009. In one embodiment, the outer ports 4010 may penetrate onlythe top major surface 4003 of the processing wedge 4002 and the innerports 4010 may penetrate only the bottom major surface 4004. In onenon-limiting implementation, eight outer ports 4010 and three innerports 4011 may be provided as illustrated. Other numbers of ports may beused in other embodiments and is not limiting of the invention. Theinner ports 4011 correspond in number and arrangement to the clusters3433 of flow passages 3434 in the fluid exchange dock 3430 (see, e.g.FIGS. 55-56), which in turn match the flow ports 3451 formed in the topsurface of centrifuge tubes 3450 for exchanging fluids when the tube hub3500 is in the upper docked position. Inner ports 4011 may be mutuallyconfigured with the top inlets to the flow passages 3434 in the fluidexchange dock 3430 to form a detachable leak-resistant sealed jointtherebetween. For example, inner ports 4011 may thus be configured withthe same type nozzles 3436 shown in FIG. 56 on the bottom of fluidexchange dock 3430 to form a detachable sealed therewith in a similarmanner.

Outer ports 4010 are configured for fluid connection to external processtubing 3021 (see, e.g. FIG. 1). In one embodiment, outer ports 4010 mayoptionally include upwardly protruding tubing barbs 4013 to facilitatethe coupling (see, e.g. FIG. 103). Alternatively, outer ports 4010 mayinstead include recessed nozzles 3436 configured similarly to the innerports 4011 which can also facilitate fluid connection to process tubing3021 without having a protruding tubing barb.

Referring to the flow diagrams of FIGS. 104-119, the inner and outerports 4010, 4011 are fluidly coupled together by a branched microchannelnetwork 4015 of microchannels 4012 formed internally within themicrofluidic processing disk 4000. On the liquid side, the microchannelnetwork forms flow paths between the inner and outer ports, and fluidlycouples the flow control microfluidic devices together embedded inmicrofluidic processing disk 4000. The flow network 4015 also includesair microchannels 4012 which forms air connections to the liquidmicrochannels and microfluidic flow control devices by the pneumaticsystem which may include sources of high pressure and low pressure airas shown. Pressurized air provided by air compressor 3000 (example shownin FIG. 1) or another compressor/compressors provides the motive forcefor flowing and processing the foregoing fluids through the microfluidicprocessing disk 4000 in accordance with the flow diagrams and asdescribed herein.

The microchannels 4012 (air and liquid) of each processing wedge 4002are configured and patterned to form the functional layout and fluidconnections represented in the flow diagrams of FIGS. 104-119(recognizing that the physical layout may differ to create thefunctional connections shown). The blocks on the left of this figurerepresent the outer ports 4010 and those on the right represent theinner ports 4011 of each processing wedge 4002. It is well within theambit of a microfluidic device manufacturer to create the depicted flownetwork (and flow control microfluidic devices shown) usingcomputer-aided fabrication methods without undue further elaborationhere. The microchannels 4012 may be formed in one or more of the layersof the microfluidic processing disk by any suitable process orcombination of processes commonly used to construct microfluidicdevices, such as for example without limitation micro-machining, lasermilling, laser or chemical etching, lithography, hot embossing,injection molding, or other.

The microchannel network 4015 further includes a plurality ofmicrofluidic valves, pumps, mixing chambers shown in FIGS. 104-119. Inone embodiment, these microfluidic devices may be diaphragm operated andcreated using a flexible elastomeric flow control layer embedded withinthe microfluidic processing disk 4000 which is in communication with themicrochannels and chambers created within the microfluidic processingdisk 4000, as described elsewhere herein. The microfluidic devices mayfurther include pneumatically-actuated diaphragm micropumps includingextractant pump 4020, slurry pump 4021, reagent pump 4022, and transferpump 4023. The microchannels 4012 are opened/closed by a plurality ofpneumatically-actuated diaphragm microvalves 4018 schematicallyrepresented by circles (solid circle=closed; open circle=open).Pneumatically-actuated micro-mixing chambers 4024 may optionally beprovided as required for mixing soil sample slurry with extractant,and/or upstream of the flow analysis cell 4027 and flow cell window 4025each integrated into the processing wedge 4002 to ensure complete mixingof the color changing reagent (also sometimes referred to as“indicator”) and supernatant if required. In some embodiments, themicro-mixing chambers 4024 may be formed by two closely fluidly coupledcells connected via a narrow short microchannel which is well knownconstruction in the microfluidic arts. The cells are alternatinglypressurized by air to cyclically transfer the liquid back and forthmultiple times between the cells, thereby providing thorough mixing.They mixers may or may not be diaphragm operated. It will be appreciatedthat other types of microfluidic mixers, pumps, and valves however maybe used and the invention is not limited to the disclosed non-limitingexamples.

FIGS. 256 and 257-258 are exploded and side cross-sectional viewsrespectively of an on-disk pneumatically-actuated diaphragm micropump5760, which may be used for the extractant pump 4020, slurry pump 4021,reagent pump 4022, transfer pump 4023, or other pumps that may berequired. These pumps are incorporated into the microchannel network4015 of each disk processing wedge 4002 and apply the motive force tothe fluid to drive it through the microchannel network and variousflow-related features of the disk. The micropumps and features shown areeach integrally formed or molded within two adjacent layers of eachwedge 4002 as unitary structural portions thereof. The illustration inFIG. 256 depicts a portion of the disk which includes the micropumprecognizing that in actuality the micropumps are only defined byboundaries of the openings and/or concave structures formed directly inthe disk layers.

Each micropump 5760 is a sandwiched structure including an upper layer5761 of the microfluidic processing disk 4000, adjacent lower layer 5762of the disk, and a thin resiliently deformable diaphragm 5763 having anelastic memory and defining a top surface 5763-1 and opposing bottomsurface 5763-2. It bears particular note that the upper and lower layers5761, 5762 are not necessary the uppermost (i.e. top) and lowermost(i.e. bottom) layers of the multi-layered microfluidic processing disk4000, but instead may be two adjacent intermediate layers therebetween.In one non-limiting embodiments, the upper and lower layers 5761, 5762are intermediate layers in a 5-layer processing disk 4000.

The diaphragm 5763 may be made of a suitable elastomeric material orpolymer, such as silicone in some embodiments, and may have thicknessesless than 1 mm (0.04 inches). Diaphragm 5763 is resiliently movablebetween a normally flat standby condition when no pneumatic air pressuresignal is applied and a deformed downwardly projecting convex actuatedcondition when air is applied to the top surface of the diaphragm. Thediaphragm 5763 may be oval in one configuration; however, other shapesmay be used.

The micropump 5760 further includes an upper pump chamber 5764 recessedinto the bottom surface of the upper layer 5761 of microfluidicprocessing disk 4000, and a concavely shaped lower pump chamber 5765directly opposing and vertically aligned with the upper chamber formedin the lower layer 5762. The upper chamber 5764 may have straightsidewall surfaces 5764-1 and a flat top surface 5764-2 in someembodiments. Lower chamber 5765 is recessed into the top surface oflower layer 5762 and may include arcuately curved sidewall surfaces5765-1 which extend perimetrically around the chamber. A flat bottomsurface 5765-2 adjoins the sidewall surfaces around the perimeter of thelower chamber as shown. The curved sidewall surfaces ensure that thediaphragm 5763 does not tear or crack when actuated over multipleoperating cycles. It bears noting that the lower chamber 5765 definesthe volumetric pumping capacity of the micropump which is expelled witheach actuation of the micropump.

The micropump 5760 further includes a pneumatic air pressure signal port5768 formed in upper layer 5761 which in fluid communication with theupper chamber 5764. Port 5768 is preferably centered in the top surfaceof the upper chamber 5764 and in fluid communication with a pneumatic orair microchannel network 4015-1 formed in the disk layer immediatelyabove the upper layer 5761 and fluidly coupled to an air source such asthose described herein. The lower layer 5762 includes a fluid inlet port5766 for introducing fluid into the lower chamber 5765, and a fluidoutlet port 5767 for discharging fluid from the lower chamber causes byoperation of the micropump 5760. Each port 5766, 5767 is thus in fluidcommunication with the lower chamber 5765. The fluid inlet port 5766preferably penetrates the lower chamber 5765 at an opposite end of thechamber than its outlet port 5767 at the other end. Each of the fluidinlet and outlet ports is in fluid communication with the fluidmicrochannel network 4015 formed in the disk layer immediately below thelower layer 5762. In one embodiment, the upper and lower chambers 5761,5762 may be oval shaped; however, other shapes may be used.

Operation of micropump 5760 will be briefly described. Each micropumphas an associated fluid inlet diaphragm microvalve 4018 and fluid outletdiaphragm microvalves 4018 fluidly coupled to the fluid inlet and outletports 5766, 5767 respectively which are necessary for operation of themicropump. The diaphragm valves have the same general construction andoperation as the micropumps including a diaphragm, air pressure signalport, and fluid inlet and outlet ports. Operation of the valves betweenan open and closed position is performed in the same manner as describedbelow for the micropumps which are thus analogous in structure andfunction to the valves. The valves however are generally smaller in sizedue to the multitude of valves arranged in the microfluidic processingdisk 4000 to conserved space, and typically utilize circular diaphragmsand upper and lower chambers in contrast to the elongated features ofthe micropumps intended to hold a predetermined volume of fluidnecessary for the chemical processes and soil analysis. A single controlsignal can command simultaneous actuation of a pump(s), a valve(s), or apump(s) and valve(s) in a plurality of manifolds. A single controlsignal can command simultaneous actuation of a plurality of pumps, aplurality of valves, or a plurality of pumps and valves in a manifold.

FIG. 257 shows the pump in the initial flat unactuated or standbycondition. Diaphragm 5763 is fully nested inside upper pump chamber 5764and does not project downwards into lower pump chamber 5765. Thediaphragm is trapped in the upper chamber 5764 between the upper andlower disk layers 5761, 5762. No air is applied to the diaphragm at thisstage. The fluid outlet diaphragm microvalve 4018 is first closed andthe fluid inlet diaphragm valve is opened to fill the lower chamber 5765beneath the diaphragm with the fluid to be pumped from the microchannelnetwork 4015 (e.g. soil slurry, extractant, reagent, supernatant, orother fluid). The fluid inlet diaphragm microvalve 4018 is then closedand the fluid outlet diaphragm microvalve 4018 is opened.

To pump the fluid volume contained in the lower pump chamber 5765, airis supplied to the top of the diaphragm 5763 via the air pressure signalport 5768 from the air source which is controlled by an air valve. Theair pressure drives the diaphragm downward, which deforms and generallyconforms to the shape of the lower chamber 5765, thereby expelling thefluid through the fluid outlet port 5767 and its associated outletmicrovalve 4018. The diaphragm 5763 is now in the deformed convexactuated condition shown in FIG. 258. After pumping is completed, theair pressure is relieved from the air pressure signal port 5768 and thediaphragm 5763 returns to its original undeformed flat standby conditionready for the next pumping cycle.

In testing, it was discovered that if smooth surfaces are providedwithin the lower pump chamber 5765 (left screenshots), the flexiblediaphragm 5763 tends on occasion to get sucked into the fluid outletport 5767 for either the pneumatic signal or fluid liquid-sidecommunication prematurely. This unfortunately blocks fluid flow andpumping before the diaphragm is fully displaced/deformed and preventsthe liquid volume in the lower chamber from being fully expelled. Thiscauses inconsistency in the volume of fluid pumped per actuation, whichcan adversely affect proper slurry processing and analysis since thevolumetric capacity for each pumping chamber is carefully predeterminedand exacting to ensure the proper ratio of chemicals (e.g. reagent,extractant, etc.) are mixed with the slurry.

To combat the foregoing diaphragm and pumping problems, the concavelower pump chamber 5765 preferably is provided with a plurality of“anti-stall” grooves 5769 which act to keep the flexible diaphragm 5763from getting sucked into the fluid outlet port 5767 and blocking flow.This also prevents the diaphragm from attaching via formation of suctionto but not fully releasing from the generally flat bottom surface 5765-2of the lower pump chamber. The anti-stall grooves 5769 are thereforeconfigured to prevent adherence of the diaphragm 5763 to the lower pumpchamber 5765, thereby advantageously allowing the diaphragm 5763 tofully and reliably displace substantially the entire volumetric fluidcontents of the lower chamber with each pumping cycle, thereby ensuringaccuracy of the amount of fluid dispensed and ultimate soil slurryanalysis. The recessed anti-stall grooves 5769 are cut or otherwiseformed into preferably all surfaces within the lower chamber 5765 (e.g.sidewall surfaces 5765-1 and flat bottom surface 5765-2), as shown inFIG. 256. In one embodiment, the grooves 5769 may be arranged in atwo-directional perpendicularly intersecting grid array of grooves asshown forming a somewhat checkerboard pattern. In other embodiments, thegrooves may be unidirectional and formed by a plurality ofnon-intersecting and spaced apart parallel grooves arranged either alongthe major axis or minor axis of the lower chamber 5765, or diagonally tothe axes. In some embodiments, the upper pump chamber 5764 formed in theupper disk layer 5761 may include anti-stall grooves similar to ordifferent in configuration than the grooves in the lower chamber 5765.Any suitable pattern and number of grooves may be provided.

The microchannel network 4015 may further include a plurality ofmicroreservoirs of predetermined volume for holding and staging theextractant, reagent, slurry, etc. for processing. In one embodiment,this may include an extractant microreservoir 4030, soil slurrymicroreservoir 4031, reagent microreservoir 4032, and supernatantmicroreservoir 4033. The microreservoirs 4030-4033 may be formed by aseries of closely spaced, undulating loops of microchannels as shown.Sample non-limiting volumetric capacities of each microreservoir areshown in FIGS. 104-119. Other volumetric capacities, however, may ofcourse be used.

FIGS. 104-119 are schematic flow diagrams depicting sequential views ofa method or process for processing and analyzing a soil sample. Thesediagrams represent the processing sequence which occurs in a singleprocessing wedge 4002 of microfluidic processing disk 4000. It will beappreciated that in some implementations of the method, the samesequential process shown is performed simultaneously in parallel in allof the processing wedges 4002 of processing disk 4000 to analyze thesoil sample slurry for all chemical parameters of interest (analytes),thereby resulting in a significant reduction in sample processing time.Accordingly, the same corresponding pneumatically-actuated micropumps,microvalves, and micro-mixing chambers in each processing wedge 4002 maybe actuated simultaneously via a common control air header or channeland air valves. Each processing wedge 4002 may therefore process andanalyze the sample for a different analyte to complete the full chemicalanalysis profile of the soil sample.

The process described below and in the flow diagrams may beautomatically controlled and executed by the system programmablecontroller, such as for example processing system 2820 disclosed incopending U.S. patent application Ser. No. 15/806,014 filed Nov. 7,2017. The controller is operably coupled to the low and high pressureair supply, such as air compressor 3030 and air tank 3031 (see, e.g.FIG. 1). The low pressure air may be created in any suitable knownmanner such as by employing a pressure reducing valve station takingsuction from the air tank 3031, which may contain high pressure airproduced by the compressor 3030. All air supply related components(compressor, tank(s), and valves) may therefore be controlled by thesystem programmable controller (e.g. processing system 2820). Othersources of low and high pressure air for pneumatically controllingoperation of the microfluidic processing disk 4000 such as separatecompressors may of course be used.

In the flow diagrams, it bears noting that the emboldened and thickerdark lines represent the active fluid flow paths during each of theprocess sequences shown and described. Valve position of thepneumatically-actuated diaphragm microvalves 4018 are schematicallyrepresented by solid or open circles (solid circle=closed; opencircle=open).

To reiterate, as previously noted, the blocks on the left of the flowdiagrams represent the outer ports 4010 of the respective processingwedge 4002 and blocks on the right represent the inner ports of thewedge. In one implementation, the outer ports 4010 may include a highpressure air inlet 4010-1, low pressure air inlet 4010-2 also configuredto operate as an air vent when required, extractant inlet 4010-3,cleaning solution 4010-4, slurry sample inlet 4010-5, reagent(indicator) inlet 4010-6, low pressure exhaust outlet 4010-7, and highpressure exhaust outlet 4010-8. The cleaning solution provided to inlet4010-4 may be any suitable solution including deionized water or other.The inner ports 4011 may include a slurry sample outlet 4011-1 fromprocessing wedge 4002 to centrifuge 3400 (i.e. centrifuge tube 3450),supernatant inlet 4011-2 from centrifuge 3400, and centrifuge wasteinlet 4011-3 from the centrifuge. Other types and numbers of outer andinner ports 4010, 4011 may of course be provided.

FIG. 104 shows the provision of the microfluidic processing disk 4000and processing wedge 4002 with microchannel network 4015 at the startand readied for processing and chemically analyzing a soil sample. InFIG. 105, the soil slurry sample from the mixing station previouslydescribed herein (e.g. mixer-filter apparatus 100 or 200) and extractantfrom extractant tank 3308 (see, e.g. FIG. 1) are pumped into thesample/extractant measurement loops (reservoirs) to fill microreservoirs4030 and 4031 at a precise predetermined ratio of slurry to extractant.It bears noting that the low pressure exhaust path to outlet 4010-7 isopened briefly to not only drive any air from the active microchannels4012, but to also very briefly discharge some of the slurry andextractant to waste to ensure the microreservoirs 4030, 4031 arecompletely filled before shutting off the slurry and extractant sources.Also noteworthy are closed/open valving 4018 positions in these and theremaining flow diagrams which open and close various flow paths in themicrochannels 4012 of microchannel network 4015.

In FIG. 106, the slurry sample and extractant measurement loops(reservoirs) are pumped together into an optional first micro-mixingchamber 4024 where they are mixed. In some situations, adequate mixingof the sample and extractant may be achieved within the microchannels4012 to obviate the need to a separate micro-mixing chamber (hencedesignation of the same with a “?” in the figure). Diaphragm-operatedmicropumps 4020, 4021 are pressurized with low pressure air as shown toachieve pumping of the fluids. In FIG. 107, complete mixing of theslurry sample and extractant is performed. In FIG. 108, theextractant/sample mixture is pumped from first micro-mixing chamber 4024to the centrifuge 3400 for processing. In FIG. 109, supernatant andreagent are staged and pumped into their respective measurement loops(i.e. microreservoirs 4033 and 4032 at a precise predetermined ratio ofsupernatant to reagent. Some supernatant and reagent are very brieflydumped to waste via the flow path to lower pressure exhaust outlet4010-7 to ensure these microreservoirs are completely filled. In FIG.110, the supernatant and reagent are pumped to a second micro-mixingchamber 4024. Note that the microchannel flow path comprising themicro-mixing chamber 4024, de-bubbler 4026, and flow cell window 4025are active and fluidly connected to low pressure exhaust outlet 4010-7.In FIG. 111, complete mixing of the supernatant and reagent is performedin the second micro-mixing chamber 4024, thereby causing a color changein the solution for detection by the absorbance analysis flow cell 4027via downstream flow cell window 4025. In FIG. 112, the supernatant andreagent mixture incorporating the analyte therein is pumped through thede-bubbler 4026 in the de-bubbling station which removes any residualair bubbles entrained in the mixture. Bubbles in the liquid stream maycause volume anomalies in the downstream flow analysis cell 427 andadversely affect analytical accuracy. De-bubblers are well known devicesin the art without further undue elaboration.

In FIG. 113, the supernatant/reagent mixture incorporating the analyteis pumped into flow cell window 4025 of absorbance flow analysis cell4027 for colorimetric measurement by the absorbance flow analysis cell4027 in a similar manner to that previously discussed herein in relationto absorbance flow analysis cell 3800 (see, e.g. FIG. 77). In contrastto flow analysis cell 3800, the present flow analysis cell 4027 isformed integrally with and incorporated directly into a portion ofprocessing wedge 4002. FIGS. 120 and 121 schematically depict theportion of wedge 4002 containing absorbance flow analysis cell 4027 andflow cells window 4025 formed within the bonded layer structure of theprocessing wedge. In the exemplary non-limiting construction shown, thelayers comprises three hard plastic layers 4000-1 (e.g. PC, etc.)forming a top layer, bottom layer, and intermediate patterned with theforegoing microchannels and other fluid control devices such as themicropumps, microvalves, and micro-mixing chambers. The thin flexibleelastomeric layer 4000-2 (e.g. silicon, etc.) is formed immediately ontop of the intermediate hard layer 4000-1 for functioning as a diaphragmof the fluid control devices. In one embodiment, flow analysis window4025 may be a laterally widened diamond-shaped chamber (see, e.g. FIG.121). An LED emitting diode assembly 4040 and LED receiving diodeassembly 4041 are mounted above and below the flow analysis window 4025respectively. Diode assemblies 4040, 4041 are attached to the outmosttop and bottom surfaces of processing wedge 4002 above and below window4025 as shown, but fluidly isolated from the window and liquid flowstream in the processing wedge 4002. Layer 4000-2 may have a cutoutformed directly above flow analysis window 4025 corresponding in sizeand shape to the emitting diode assembly 4040 to avoid possiblereflective/refractive interference with the emitted analysis light beam.

In operation, the liquid reagent and supernatant mixture flows throughflow analysis window 4025 (see, e.g. solid liquid flow arrows). As theflow passes through the window 4025, the emitting diode assembly 4040transmits and shines light through the window and liquid therein to thereceiving diode assembly 4041 for colorimetric measurement in a knownmanner. The measurement of the analyte in the sample mixture liquidstream is transmitted to the system programmable controller for analysisand quantification. During the analysis, it bears noting that the samplemixture flows continuously through the flow cell window 4025 to the lowpressure exhaust outlet 41010-7 where it is then dumped to waste.

It bears noting that the micro-mixing chambers 4024 described above maybe omitted in some instances if complete mixing can be achieved withinthe microchannels themselves. The micro-mixing chambers 4024 aretherefore optional for use when required.

After the soil sample has been fully processed in the above manner, thesystem programmable controller is configured to initiate a cleaningcycle to prepare the microfluidic processing disk 4000 for processing anew soil sample. In FIGS. 114-117, cleaning solution and low pressureair are each selectively and alternately pumped into and through theemboldened active sample loop microchannels 4012 and through thecentrifuge 3400 to the high pressure exhaust outlet 4010-8 as shown.This clears residual soil slurry and chemicals from these components andmicrochannels. After several cycles of alternating cleaning solution andpurge air is processed through the microchannels and centrifuge, FIG.118 shows that at this point, the sample loop and flow paths upstream ofthe emboldened segment of the sample loop microchannels has only air init. There is a column containing a mixture of air and cleaning solutionremaining in the emboldened section of flow path. In FIG. 119, themicrovalves 4018 shown open to allow high pressure air from highpressure air inlet 4010-1 to force the air/cleaning solution mixturecolumn (emboldened) through the centrifuge 3400. The high pressure airthen purges the centrifuge and flows to the high pressure exhaust outlet4010-8, which completes the cleaning cycle.

In other embodiments, it will be appreciated that separate and discreteabsorbance analysis cells such as standalone absorbance flow analysiscell 3800 or other configurations may be used in lieu of the integralabsorbance flow analysis cell 4027 incorporated into the chemicalprocessing wedge of microfluidic processing disk 4000. Advantageously,the integral absorbance flow analysis cell 4027 results in a greatercompactness of the centrifuge 3400 by eliminating spatial requirementsnecessary to accommodate discrete flow analysis cells.

Referring to FIGS. 259-260, in some embodiments the microfluidicprocessing disk 4000 may be heated to better process the soil sampleslurry, chemicals, and water by maintaining viscosity and fluidityparticularly during cooler weather and in cooler climate zones. A singleprocessing wedge 4002 with its multi-layered construction describedherein is shown. Outer ports 4010, inner ports 4011 (previouslydescribed herein), and some intermediate ports 4010-1 are shown asexamples. Chemicals and soil sample slurry are heated prior toprocessing and mixing within the slice as described above via electricresistance heating pads 4050 which heat each slice or wedge 4002 topreferably maintain constant temperature in the wedge. Pads 4050 arecomplementary configured to the wedge as shown. Preferably, a heatingpad 4050 is affixed to both the top and bottom surfaces 4051, 4052 ofeach wedge to maintain even heat distribution between the surfaces. Eachheating pad 4050 includes ports 4010, 4010-1, and 4011 which areconcentrically aligned with those same ports formed in the body of theprocessing wedge 4002. The heating pads 4050 are wired to a suitablemain electric power source provided for the soil sampling and analysissystem process equipment.

Temp sensor(s) 4054 monitor the wedge temperature and communicate viawired or wireless communication links 4055 with the heater controlcircuitry 4053, which may be local and mounted on one of the heatingpads 4050 in one embodiment. In other embodiments, the heater controlcircuitry may not be onboard and remotely located in the soil samplingand analysis system relative to the microfluidic processing disk 4000.The heater control circuitry 4053 may be communicably linked to the mainsystem programmable controller, such as for example central processingunit (CPU) 2820 via suitable wired or wireless communication links 4055to exchange real-time temperature data measured by sensors 4054 with thecontroller.

In addition to heating pads 4050 or instead of, other suitable upstreampre-slice heat exchanger(s) not attached to each processing wedge 4002could be used in certain other embodiments to preheat the slurry sample,chemicals and/or process water upstream of and before entering theindividual processing wedges 4002. As one example, the processpurified/filtered water tank 5741 shown schematically in FIGS. 264-266which supplies process water to the microfluidic processing disk 4000 orother chemical processing systems described herein could optionally beheated by one or more separate electric resistance external and/orimmersion elements or heaters 5742 for use during cooler weather.

FIGS. 122-129 depict an alternative embodiment of a standaloneabsorbance flow analysis cell 4150 usable as a substitute for cell 3800in FIG. 1. Either cell 4150 or 3800 may be substituted for the integralflow analysis cell 4027 incorporated into processing wedge 4002 shown inFIG. 104. Cell 4150 has a multi-layered composite constructioncomprising a top outer layer 4155-1, bottom outer layer 4155-5, andthree inner layers 4155-2, 4155-3, and 4155-4 arranged in verticallystacked relationship. The layers may be bonded or laminated together inthe order shown via any suitable method, including for example viaadhesives, heat fusion, ultrasonic welding, etc. Any suitablethermoplastic such as those previously described herein to constructmicrofluidic processing disk 4000 may be used. In one embodiment, eachlayer may be formed of clear acrylic.

An inlet tubing connector 4151 and outlet tubing connector 4152 providesfluid communication via flow tubing 3021 to the supernatant and reagentmixture flow tubing in FIG. 1. If used with processing wedge 4002 inlieu of integral flow analysis cell 4027 which would therefore beomitted from the wedge, the inlet tubing connector 4151 may be fluidlyconnected to a mating tubing connector on the wedge immediatelydownstream of de-bubbler 4026. The supernatant and reagent mixture fluidwould then flow directly from the de-bubbler outlet to flow analysiscell 4150 for colorimetric analysis. In one embodiment, the tubingconnectors may be configured as tubing barbs; however, other type tubingflow connectors may be used.

The supernatant and reagent mixture flows through flow ports 4156 formedin top outer layer 4155-1 and uppermost inner layer 4155-2 (see, e.g.FIG. 124). An elongated, slot-shaped flow cell 4157 is formed in themiddle inner layer 4155-3. Flow enters the inlet tubing connector 4151to one end of the flow cell 4157, traverses the window, and leaves theoutlet tubing connector 4152.

LED emitting diode probe 4040 and LED receiving diode probe 4041 fromFIG. 120 would be mounted above and below the flow analysis cell 4150 attransmission openings 4153 and 4154 in the outer layers, respectively(see, e.g. FIG. 129). Openings 4153, 4154 are complementary sized to thediode probe bodies and completely penetrate the top and bottom outerlayers to efficiently transmit the analysis light through the liquidsample flowing through the flow analysis cell. The LED probes 4040, 4041and openings 4153, 4154 are vertically aligned with the center of flowcell 4157. The flow cell 4157 may be laterally broadened creating asomewhat diamond shape in one embodiment having a width commensuratewith the diameter of the LED probes. As flow traverses the flow cell4157, the analysis light passed transversely through the flow cellwindow from the emitting diode probe 4040 to receiving diode probe 4041to perform a colorimetric of the reagent and supernatant mixture toquantify the concentration of the analyte contained therein in a knownmanner.

It bears noting that the uppermost and lowermost inner layers 4155-2 and4155-4 present a solid surface to transmission openings 4153, 4154associated with the diode probes to fluidly isolate the probes fromsupernatant and reagent mixture in the flow analysis cell 4150.

In order to accommodate the microfluidic processing disk 4000,centrifuge 3400 previously described herein is modified to permitmounting the disk 4000 on top of the motor drive mechanism 3450-1 whichis relocated to the bottom of the centrifuge beneath the rotary tube hub3500 which is coupled to the drive shaft 3700 the drive mechanism. FIGS.130-136 depict a modified centrifuge 4200 which may include a majorityof the primary centrifuge components previously described herein withrespect to centrifuge 3400; albeit some being rearranged in location asshown. Note that the shields are omitted from these figures to bettershow the operating components of centrifuge 4200.

Referring to FIGS. 130-136, centrifuge 4200 generally includes motordrive mechanism 3450-1, plurality of centrifuge tubes 3450 pivotablymounted to rotary tube hub 3500 which is mechanically coupled to thedrive shaft 3700 of the drive mechanism, stationary fluid exchange dock3430, air-operated piston mechanism 3600 for raising and lowering thetube hub, and microfluidic processing disk 4000. Motor drive mechanism3450-1 may comprise at least the main motor 3705, and in someembodiments may have the same drive assembly previously described whichfurther includes the indexing motor 3704 and the assembly of gears3707-3709 and timing belt 3713 (see, e.g. FIGS. 43-54, 76, and 95). Thedrive mechanism 3450-1 is mounted below the rotary tube hub 3500, pistonmechanism 3600, fluid exchange dock 3430, and microfluidic processingdisk 4000. Main drive shaft 3700 defines the rotational axis RA creatinga vertical centerline of centrifuge 4200 for reference purposes.

A slightly modified main support housing 4202 is provided which supportsthe foregoing components of centrifuge 4200. Housing 4202 may have thesame general configuration and members as support housing 3401previously described. Housing 4202 generally comprise a vertical mainsupport plate 4202-1, an upper support plate 4202-3, a lower supportplate 4202-2 oriented parallel to the upper support plate, andoptionally base 4202-4 for mounting on a horizontal support surfaceeither fixedly or via a plurality of vertically adjustable legs 4202-5.In some embodiments, particularly when centrifuge 4200 is mounted to aseparate support frame such as that provided with a wheeled collectionvehicle with an internal combustion engine drive that can operated tocollect soil samples from the field, base 4202-4 may be modified oromitted including the adjustable legs.

Upper and lower support plates 4202-3, 4202-2 of housing 4202 arevertically spaced apart and may be horizontally oriented as shown in theillustrated embodiment, thereby defining a partially or totally enclosedsample processing chamber 3501. Each support plate 4202-3, 4202-2 mayhave one peripheral side or end attached to vertical support plate4202-1 in a cantilevered manner via a suitable mechanical connectionmethod, such as without limitation welding, soldering, threadedfasteners, adhesives, clips, interlocking features (e.g. tabs/slots), orother and combinations thereof. In one embodiment, support plates4202-3, 4202-2 may be oriented perpendicularly to the main support plate3402 as shown.

Upper support plate 4202-3 of support housing 4202 includes a relativelylarge circular central opening 4202-6 for mounting and receiving a lowerdiametrically narrower portion of fluid exchange dock 3430 therein andtherethrough which is supported by the upper support plate (see, e.g.FIGS. 135-136). Microfluidic processing disk 4000 is mounted directly ontop of fluid exchange dock 3430 as previously described herein. Therotary tube hub 3500 assembly (including covers 3520, 3521) is mountedbelow upper support plate 4202-3. This allows the rotary tube hub 3500to be axially raised and lowered by the piston mechanism 3600 in thesample processing chamber 3501 of centrifuge 4200 between its upperdocked and lower undocked positions for exchanging fluids with thecentrifuge tubes 3450 (e.g. slurry-extractant, supernatant, or tubeflushing water-air stream) in the upper position, or alternativelycentrifugating the soil samples in the tubes in the lower position.

Fluid exchange dock 3430 may include a plurality of circumferentiallyspaced apart tube travel stops 4203 projecting downwards from the bottomsurface of the dock. Travel stops 4203 are selectably insertable intothe plurality of rectangular tube openings 3523 formed in upper andlower covers 3520, 3521 of the rotary tube hub assembly when the tubehub 3500 is lowered and raised via operation of the piston mechanism3600. With additional reference to FIG. 66, travel stops 4203 arereceived in the outer vacant portions of tube openings 3523 as bestshown in FIG. 136 when the centrifuge tubes 3450 are in a verticalposition when the tube hub 3500 is in the upper docked position engagedwith fluid exchange dock 3430. This advantageously maintains and snugglyholds the centrifuge tubes in the vertical upright position when fluidsare exchanged between the fluid exchange dock and tubes from or to themicrofluidic processing disk 4000, which ensures a tight leak-resistanceseal between dock and tubes to prevent leakage.

The operation of centrifuge 4200 is substantially the same as previouslydescribed herein for centrifuge 3400, and will not be repeated in itsentirety for sake of brevity. In sum, rotary tube hub 3500 is axiallyraised and lowered by the piston mechanism 3600 in the sample processingchamber 3501 of centrifuge 4200 between its upper docked and lowerundocked positions for exchanging fluids with the centrifuge tubes 3450(see, e.g. FIGS. 72-75). The centrifuge 4200 is rotated by motor drivemechanism 3450-1 in the same manner when rotary tube hub 3500 is in thelower undocked position to centrifugate the soil samples. The driveshaft 3700 and motor drive mechanism 3450-1 is suspended from and raisedand lowered with the rotary tube hub 3500 by the piston mechanism.

As already noted herein, the agricultural sampling system, sub-systems,and related processes/methods disclosed herein may be used forprocessing and testing soil, vegetation/plants, manure, feed, milk, orother agricultural related parameters of interest. Particularly,embodiments of the chemical analysis portion of the system (chemicalanalysis sub-system 3003) disclosed herein can be used to test formultitude of chemical-related parameters and analytes (e.g.nutrients/chemicals of interest) in other areas beyond soil andplant/vegetation sampling. Some non-limiting examples (including soiland plants) are as follows.

Soil Analysis: Nitrate, Nitrite, Total Nitrogen, Ammonium, Phosphate,Orthophosphate, Polyphosphate, Total Phosphate, Potassium, Magnesium,Calcium, Sodium, Cation Exchange Capacity, pH, Percent Base Saturationof Cations, Sulfur, Zinc, Manganese, Iron, Copper, Boron, Soluble Salts,Organic Matter, Excess Lime, Active Carbon, Aluminum, Amino SugarNitrate, Ammoniacal Nitrogen, Chloride, C:N Ratio, ElectricalConductivity, Molybdenum, Texture (Sand, Silt, Clay), Cyst nematode eggcounts, Mineralizable Nitrogen, and Soil pore space.

Plants/Vegetation: Nitrogen, Nitrate, Phosphorus, Potassium, Magnesium,Calcium, Sodium, Percent Base Saturation of Cations, Sulfur, Zinc,Manganese, Iron, Copper, Boron, Ammoniacal Nitrogen, Carbon, Chloride,Cobalt, Molybdenum, Selenium, Total Nitrogen, and Live plant parasiticnematode.

Manure: Moisture/Total Solids, Total Nitrogen, Organic Nitrogen,Phosphate, Potash, Sulfur, Calcium, Magnesium, Sodium, Iron, Manganese,Copper, Zinc, pH, Total Carbon, Soluble Salts, C/N Ratio, AmmoniacalNitrogen, Nitrate Nitrogen, Chloride, Organic Matter, Ash, Conductance,Kjeldahl Nitrogen, E. coli, Fecal Coliform, Salmonella, Total KjeldahlNitrogen, Total Phosphate, Potash, Nitrate Nitrogen, Water SolubleNitrogen, Water Insoluble Nitrogen, Ammoniacal Nitrogen, Humic Acid, pH,Total Organic Carbon, Bulk Density (packed), Moisture, Sulfur, Calcium,Boron, Cobalt, Copper, Iron, Manganese, Arsenic, Chloride, Lead,Selenium, Cadmium, Chromium, Mercury, Nickel, Sodium, Molybdenum, andZinc

Feeds: Alanine, Histidine, Proline, Arginine, Isoleucine, Serine,Aspartic Acid, Leucine, Threonine, Cystine, Lysine, Tryptophan, GlutamicAcid, Methionine, Tyrosine, Glycine, Phenylalanine, Valine (RequiresCrude Protein), Arsenic, Lead, Cadmium, Antimony, Mercury

Vitamin E (beta-tocopherol), Vitamin E (alpha-tocopherol), Vitamin E(delta-tocopherol), Vitamin E (gamma-tocopherol), Vitamin E (total),Moisture, Crude Protein, Calcium, Phosphorus, ADF, Ash, TDN, Energy(Digestible and Metabolizable), Net Energy (Gain, Lactation,Maintenance), Sulfur, Calcium, Magnesium, Sodium, Manganese, Zinc,Potassium, Phosphorus, Iron, Copper (not applicable to premixes),Saturated Fat, Monounsaturated Fat, Omega 3 Fatty Acids, PolyunsaturatedFat, Trans Fatty Acid, Omega 6 Fatty Acids (Requires Crude or Acid Fat),Glucose, Fructose, Sucrose, Maltose, Lactose, Aflatoxin (B1, B2, G1,G2), DON, Fumonisin, Ochratoxin, T2-Toxin, Zearalenone, Vitamin B2, B3,B5, B6, B7, B9, and B12, Calories, Chloride, Crude fiber, Lignin,Neutral Detergent Fiber, Non Protein Nitrogen, Selenium U.S. Patent,Total Iodine, Total Starch, Vitamin A, Vitamin D3, and Free Fatty Acids.

Forages: Moisture, Crude Protein, Acid Detergent Fiber ADF, NDF, TDN,Net Energy (Gain, Lactation, Maintenance), Relative Feed Value, Nitrate,Sulfur, Copper, Sodium, Magnesium, Potassium, Zinc, Iron, Calcium,Manganese, Sodium, Phosphorus, Chloride, Fiber, Lignin, Molybdenum,Prussic Acid, and Selenium USP.

Milk: Butterfat, True Protein, Somatic Cell Count, Lactose, OtherSolids, Total Solids, Added Water, Milk Urea Nitrogen, Acidity, pH,Antibiotic tests, and Micro-organisms.

Sample Collection Probes

Piston-Operated Sample Collection Probe

FIGS. 137-152 depict an embodiment of a ground-engaging coulter assembly5000 with a sample collection apparatus or probe mounted theretocomprising a piston-operated soil sample collection probe. Coulterassembly 5000 includes an onboard cam-operated sample collection probein the form of a piston mechanism 5020 configured and operable forcollecting soil core samples (surface and subterranean) at selecteddepths as the coulter or blade 5001 rolls and cuts through the ground,and then ejecting the cores to a collection receptacle. Coulter assembly5000 may be mounted to the frame of towed agricultural implement pulledby an engine-powered wheeled/tracked sample collection vehicle whichtraverses an agricultural field (e.g. tractor, etc.) to collect soilsamples.

Coulter assembly 5000 generally comprises a disk-shaped samplecollection coulter or blade 5001 configured to engage and cut/penetratethrough the soil 5002 to a depth DP1 below its surface 5003, a blade hub5004 for mounting the blade thereto, an outer hub collar 5007 fixedlyattached to the hub and rotatable therewith, and an annular bearing5008. A camming mechanism is provided including an annular cam ring 5006and a follower 5021 defined by the piston mechanism 5020, as furtherdescribed herein. The coulter assembly is assembled in the manner shownin the figures and further described below.

Blade 5001 is preferably formed of a suitable flat metal plate ofcircular shape, and may have a sharpened annular peripheral edge topenetrate the soil more easily. Any suitable diameter blade may be useddepending in part on the depth at which soil samples are to becollected.

Hub 5004 may be a flanged tube including a radial flanged portion 5004-3and a tubular portion 5004-2 projecting from the flanged portion.Tubular portion 5004-3 is insertable through a central opening 5005 inthe blade 5001 as shown for mounting the blade thereto. The flangedportion 5004-3 engages a first side surface 5001-2 of the blade when theblade is mounted to the hub. The tubular portion 5004-2 projectsoutwards from the opposite second side surface 5001-1 of the blade 5001and is coaxially aligned with a rotational axis RA1 of the blade definedby the central opening 5005 of the blade perpendicular to the sidesurfaces 5001-1, 5001-2. The flange portion 5004-3 of hub 5004 may befixedly attached to the blade 5001 via a plurality of threaded fasteners5001-3 (see, e.g. FIG. 139) in one embodiment insertable through matingpairs of the mounting holes 5001-4. This locks the blade 5001 to the hub5004. Hub 5004 defines an outwardly open bore 5004-1 which receives anend of an axle 5009 therein as shown in FIGS. 143 and 144. Hub 5004 maybe secured to axle 5009 via any suitable mechanical means, including setscrews, shrink fitting, or other as some non-limiting examples. One endof bore 5004-1 may be closed as shown to limit the insertion depth ofaxle 5009 in the hub.

Hub collar 5007 may similarly be a flanged tube including a radialflanged portion 5007-1 and tubular portion 5007-2 projecting axiallytherefrom. The tubular portion 5004-2 of hub 5004 is insertable throughthe tubular portion 5007-2 of collar 5007 as shown. Collar 5007 may befixed to the hub 5004 by any suitable manner such as via set screwsinserted through tubular portion 5007-2 of the collar into tubularportion 5004-2 of the hub. This ensures that the collar rotates inunison with the hub.

The annular bearing 5008 may be a spherical roller bearing, deep grooveball bearing, or set of tapered roller bearings in one non-limitingembodiment comprising an inner race or ring 5008-1 and outer race orring 5008-2 each rotatable relative to each other in conventionaloperation. Inner ring 5008-1 is fixedly coupled (e.g. screwed/bolted) toflanged portion 5007-1 of collar 5007 (not fastener holes) and rotateswith the collar and blade hub 5004. The tubular portion 5007-2 of thecollar is inserted through central opening 5008-3 of bearing 5008. Theinner ring 5008-1 represents the rotating part of the bearing. The outerring 5008-2 is fixed coupled to cam ring 5006 and represents thestationary part of the bearing. The inner and outer rings 5008-1, 5008-2are mutually and slideably engaged in a typical manner via an annularbearing surface interface therebetween.

Cam ring 5006 is configured for fixed attachment to the frame of thewheeled collection vehicle such as via mounting bracket 5010. Cam ring5006 and bearing outer ring 5008-1 therefore remain stationary and fixedin position relative to the frame, inner ring 5008-2, and theblade-hub-collar assembly as the blade 5001 is pulled through the soil.Bracket 5010 may have any suitable configuration including a T-shape asshown. The bracket 5010 may be bolted to the cam ring 5006 and the frameof the collection vehicle in one embodiment (note fastener holes).

Cam ring 5006 has a generally planar annular body comprising a centralopening 5006-4, first major surface 5006-1, opposing second majorsurface 5006-2 parallel to the first major surface, and a peripheralsides 5006-3 extending between the surfaces. First major surface 5006-1may be plain in one embodiment. The second major surface 5006-2 facesthe blade 5001 when assembled and defines a circumferentially-extendingannular cam track 5006-5 recessed into the surface. Cam track 5006-5extends a full continuous 360 degrees around the central opening 5006-4of the cam ring and is spaced between the central opening and peripheralsides 5006-3.

Referring particularly to FIGS. 145-146, the cam track 5006-5 generallydefines pear-shaped cam lobe profile of asymmetrical configurationincluding a base curve portion 5006-6 (extent represented by dashedline) uniformly spaced radially apart from the central opening 5006-4 bya first radial distance D1, and a nose or lobe portion 5006-7 (extentrepresented by dashed line) defining an arcuately curved apex 5006-8.The part of lobe portion 5006-7 containing the apex is spaced radiallyoutwards from the base curve portion and farther from the centralopening by a second radial distance D2 larger than distance D1. D2 mayrepresent a maximum distance and D1 may represent a minimum distance. Inone embodiment, a transition portion 5006-9 of cam track 5006-5 may beprovided between the base curve and lobe portions 5006-6, 5006-7 inwhich the radial distance varies between the first and second distancesD1, D2. The lobe portion 5006-7 may be located in one quadrant of thecam ring 5006 while the base curve and transition portions may occupythe majority of the remaining three quadrants as shown.

Cam ring 5006 may have a monolithic unitary construction in oneembodiment with cam track 5006 recessed into one side of the ring aspreviously described herein. In other embodiments, the cam ring 5006 maybe an assembly of discrete annular outer and inner ring members affixedin a rigid manner to a common annular backing plate (see, e.g. cam ring5506, FIGS. 208-210). The ring members are spaced radially apart todefine the cam track 5006-5. Reference is made to description of camring 5506 herein for further details of a cam ring assembly.

The cam track 5006-5 actuates the piston mechanism 5020 in thecollection and ejection of soil sample cores captured by the blade 5001.Piston mechanism 5020 includes an elongated soil sample collectionsleeve or cylinder 5022 with open internal through passage extendingbetween its ends and an elongated piston rod 5023 which slideably movesin a linear and radially reciprocating manner back and forth inside thecylinder when actuated by the cam track in cam ring 5006. Collectioncylinder 5022 is fixedly mounted to blade 5001 in an elongated radialslot 5024 formed in the blade. Cylinder 5022 may be welded to the bladein one construction. Thus the piston mechanism 5020 rotates with theblade 5001 for capturing soil sample cores. Slot 5024 may be a throughslot in one embodiment penetrating both major surfaces 5001-1, 5001-2 ofthe blade. The slot 5024 defines a radial actuation axis AA along whichpiston rod 5023 reciprocates within the cylinder 5022. Axis AAintersects the center of the blade central opening 5005 and isperpendicular to rotational axis RA1. The collection cylinder 5022 mayprotrude above the major surfaces 5001-1, 5001-2 of blade 5001 tofacilitate capturing a soil plug or core (see, e.g. FIG. 143).

Cam follower 5021 is fixedly disposed on the inside end 5023-1 of pistonrod 5023 and operably engages the cam track 5006-5. Follower 5021 may beT-shaped in one embodiment having opposite ends that similarly protrudeabove the major surfaces 5001-1, 5001-2 of blade 5001; one of the endsbeing inserted the cam track (see, e.g. FIG. 148). The cam follower 5021may be cylindrical and oriented perpendicularly to piston rod 5023. Atubular bushing 5025 may be rotatably disposed on the cam follower tointerface with the cam track 5006-5. Bushing 5025 thus provides smoothrolling/sliding engagement with the cam track 5006-5 as the followermoves around and through the track as the blade 5001 rotates, therebycausing the piston rod 5023 to reciprocate linearly back and forth inposition based on the shape of the cam track (noting cam ring 5006remaining stationary as previously described herein). The follower andcam track transform rotary motion of the blade 5001 into linear motionof the piston rod 5023 for capturing and ejecting the soil core from thecollection cylinder 5022.

The outside end 5023-2 of piston rod 5023 may be diametrically enlargedrelative to adjoining portions of the rod. During operation of the rod5023 as the blade 5001 rotates, the outside end 5023-2 selectively opensor closes the outside soil collection end 5022-2 of the collectioncylinder 5022 and a pair of transverse holes 5022-1 therein. Thecylinder outside end is spaced inward from the outer end 5024-2 ofradial slot 5024 to form an open gap or recess 5024-3 in blade 5001 toallow soil to enter or be ejected from the outside end 5023-2 ofcylinder 5022. The inside end 5024-1 of the slot may intersect thecentral opening 5005 of blade 5001 in one embodiment. A tubular rodretaining end cap 5026 may be mounted to the inside end 5022-3 ofcylinder 5022 to retain the rod 5023 therein. End cap 5026 has a throughbore than the enlarged outside end 5023-2 of the piston rod 50223 forthat purpose. The remaining portions of the rod are thus diametricallysmaller than the through bore to allow the rod to slide back and forththrough the end cap 5026.

Operation of the coulter assembly 5000 for capturing and ejecting a soilsample will now be described with reference to FIGS. 149-152. FIG. 149Ashows the sample collection piston mechanism 5020 in a first operatingposition. The collection cylinder 5022 of the piston mechanism islocated above the surface 5003 of the ground or soil 5002 at this pointas the blade 5001 rotates through the soil (see rotational directionarrows in these figures). The cam follower 5021 is shown just leavingthe transition portion 5006-9 of cam track 5006-5 in the cam ring 5006.As shown in FIG. 149B, the piston rod 5023 is in a flush position viaoperation of the follower 5021 such that the outside end 5023-2 ofpiston rod is flush with outside end 5022-2 of the cylinder 5022. Thiscloses the otherwise end 5022-2 of cylinder 5020 to prevent soil fromentering the cylinder.

FIG. 150A shows the blade 5001 rotated further with the samplecollection piston mechanism 5020 in a second operating position. In thisposition, the collection cylinder 5022 is below the surface 5003 of thesoil. The cam follower 5021 is shown now in the base curve portion5006-6 of cam track 5006-5. Because the base curve portion 5006-6 iscloser to central opening 5005 of blade 5001, this pulls the piston rod5023 radially inwards within the cylinder 5022. As shown in FIG. 150B,the piston rod 5023 is now in a retracted position via operation of thefollower 5021 such that the outside end 5023-2 of piston rod is nolonger flush with and instead recessed within the outside end 5022-2 ofthe cylinder 5022 (note rear transverse hole 5022-1 is now visible dueto absence of the piston rod end). A void is therefore created in theterminal outside end 5022-2 of cylinder 5022 which defines a collectionport so that soil will enter the cylinder to fill the void, therebycapturing a soil plug or core as the piston mechanism is driven into theground (see soil directional arrow). The timing of when exactly thishappens (i.e. piston rod 5023 retracts to open the end 5022-2 ofcylinder 5022) can be adjusted by changing the shape and length of thevarious portion of cam track 5006-5 in order to change the soil samplecollection depth. Collection depth could also be varied by providingmultiple piston mechanisms circumferentially spaced around the blade5001 with cylinders of different radial lengths. This would change wherethe collection end of the cylinders each fall relative to a radialdistance from the central opening of the blade 5001. In someembodiments, a plurality of sample collection piston mechanisms 5020with cylinders 5022 of different lengths may be provided.

FIG. 151A shows the blade 5001 rotated further with the samplecollection piston mechanism 5020 in a third operating position. In thisposition, the collection cylinder 5022 is again above the surface 5003of the soil. The cam follower 5021 however remains within the base curveportion 5006-6 of cam track 5006-5. As shown in FIG. 151B, the pistonrod 5023 remains in the retracted position with the soil core remainingstuck in the outside end 5022-2 of the cylinder 5022 (note reartransverse hole 5022-1 is now visible due to absence of the piston rodend). A void is created in the end 5022-2 of cylinder 5022 so that soilwill enter the cylinder to fill the void and is captured as the pistonmechanism is driven into the ground (see soil directional arrow). Thetiming of when exactly this happens (i.e. piston rod 5023 retracts toopen the end 5022-2 of cylinder 5022) can be adjusted by changing theshape and length of the various portion of cam track 5006-5 in order tochange the soil sample collection depth.

FIG. 152A shows the blade 5001 rotated further with the samplecollection piston mechanism 5020 in a fourth operating position. In thisposition, the collection cylinder 5022 is still below the surface 5003of the soil. The cam follower 5021 is shown now in the lobe portion5006-7 of cam track 5006-5. Because the lobe portion 5006-7 is farthestfrom central opening 5005 of blade 5001, this pushes the piston rod 5023radially outwards within the cylinder 5022. As shown in FIG. 152B, thepiston rod 5023 is now in a projected position via operation of thefollower 5021 such that the outside end 5023-2 of piston rod is extendsbeyond the outside end 5022-2 of the cylinder 5022, thereby effectivelyejecting the captured soil plug or core (see soil directional arrow)which in turn is collected by a collection receptacle for furtherprocessing and analysis using other portions of the mixing and chemicalanalysis systems described herein.

Rotatable Shaft Sample Collection Probe

FIGS. 153-178B depict an embodiment of a ground-engaging coulterassembly 5100 for collecting soil samples with an onboard samplecollection apparatus or probe in the form of a rotatable collectionshaft 5101. A plurality of angularly spaced apart collection shafts maybe provided. Each collection shaft 5101 rotates about a radial axis ofrotation relative to the coulter or blade 5001 of the assembly, andincludes one or more openable/closeable collection ports 5102 actuatedby a sprocket mechanism 5103 to alternatingly open and close thecollection ports, as further described herein. The ports 5102 arearranged to retrieve soil sample plugs or cores at different preselecteddepths as the coulter blade rolls and cuts through the ground. The coresare then ejected/extracted from the collection shaft 5101 andtransferred to a collection receptacle. Coulter assembly 5100 may bemounted to the frame of or trailer pulled by an engine-powered wheeledsample collection vehicle which traverses an agricultural field (e.g.tractor, etc.) for collecting soil samples.

Coulter assembly 5100 generally comprises many of the same components ascoulter assembly 5000 previously described herein. This includes thedisc-shaped body or blade 5001, blade hub 5004 for mounting the bladethereto, outer hub collar 5007 fixedly attached to the hub and rotatabletherewith, and annular bearing 5008. These components will not bedescribed again here for sake of brevity. The present coulter assemblyis assembled in the manner shown in the figures and further describedbelow.

Collection shaft 5101 may have an elongated solid cylindrical bodyincluding a plurality of laterally open collection ports 5102 spacedaxially apart along its length. Collection ports 5102 may be throughports open from two opposing sides of the shaft 5101 as shown. Theremaining two sides of the shaft are solid and closed. Ports 5102 may bein the form of radially elongated slots in the illustrated embodiment;however other shaped ports including round ports may be provided. Anynumber of collection ports 5102 may be provided depending on the numberand depths of soil samples desired.

Collection shaft 5101 is mounted to blade 5001 and rotatableindependently relative to the blade in an elongated radial slot 5107.Thus the shaft 5101 is supported by and angularly rotates with the blade5001 as it moves through the soil for capturing soil sample cores.However, the collection shaft 5101 also rotates independently of theblade 5001 about its own rotational axis Rc for selectively collectingsoil samples depending on the shaft's rotational position. Slot 5107 maybe a through slot in one embodiment penetrating both major surfaces5001-1, 5001-2 of the blade. The slot may be generally T-shaped in oneembodiment having a contiguous wider lateral portion 5107-1 at theinside end of the slot than the longer straight radial portion 5107-2.

The radial centerline of the slot 5107 defines radially-oriented axis ofrotation Rc of the collection shaft 5101, which is perpendicular to theaxis of rotation RA1 of the blade 5001 defined by axle 5009 attached toblade hub 5004. Axis Rc intersects the center of the blade centralopening 5005.

Collection shaft 5101 is rotatably supported on blade 5001 in slot 5107by an inboard and outboard bearing 5106 disposed at each end of theshaft. Any suitable type bearing including cylindrical bushings may beused to support the shaft. A pair of radially elongated guide shields5108 may be provided; one each of which is mounted on opposite sides ofthe slot 5107 (either within the slot or adjacent thereto). Shields 5108may mounted substantially flush with the major surfaces 5001-1, 5001-2of blade 5001, or protrude slightly above the major surfaces as shown inthe illustrated embodiment. The shields 5108 may be formed by flat metalstrips spot welded or otherwise fixedly attached to the blade 5001 oneach side of the slot. The collection shaft 5101 is rotatable disposedbetween the shields 5108. Bearings 5106 may in turn be fixedly mountedto the shields 5108, and the collection shaft 5101 is rotatablysupported by the bearings as noted before. The shields 5108 helpproperly position and locate the collection shaft 5101 and/or thebearings (e.g. bushings) on blade 5001 within the slot 5107. Notably,the guide shields also advantageously help shield and block thecollection ports 5102 in shaft 5101 when rotated to a closed position toprevent soil from entering the ports when not wanted for collection.

Collection shaft 5101 is rotatable between an open position in which thecollection ports 5102 are open for capturing soil, and a closed positionin which the collection ports are closed to preclude soil from enteringthe collection ports. In the open position, the collection ports 5102 ofcollection shaft 5101 may protrude at least slightly above the guideshields 5108 to facilitate entry of the soil sample into the collectionports 5102. Further, in the open position, the collection ports 5102 ofshaft 5101 face outwards away from the slot 5107 and are exposed forcapturing soil for either side of the dually open ports. In the closedposition when a soil sample is not desired, the collection ports ofshaft 5101 face inwards towards the opposing sides of slot 5107 and theplane of the blade 5001. This exposes the solid sides of the collectionshaft to the soil which precludes soil from entering the collectionports 5102. Further, in the closed position, the collection shaft 5101may be configured with a non-circular transverse cross section at leastat the port locations so its outer profile is partially or substantiallyflush with the guide shields 5108 to further prevent soil from workingits way into the collection ports 5102 beneath the shields 5108.Accordingly, in one non-limiting embodiment the opposing solid sides ofthe collection shaft 5101 may be planar or flat, and the open sides ofthe shaft with collection ports 5102 may be arcuately curved and convexto enhance the foregoing functionality of capturing soil samples.

To actuate and rotate the collection shaft 5102 between its open andclosed positions, a rotary mechanism such as sprocket mechanism 5103 isprovided to rotate the collection shaft 5101 for selectively collectingsoil samples at predetermined depths. Sprocket mechanism 5103 in oneembodiment includes an annular cam timing or indexing ring 5104 and asprocket 5105 fixedly attached to the inside end of the collection shaft5101 at the inboard bearing 5106 which engages the ring. Indexing ring5104 is fixedly mounted to the frame of the engine-powered wheeledsampling vehicle via bracket 5101 as previously described herein(similarly to cam ring 5006). The indexing ring 5104 thus remainsstationary as the blade 5001 and collection shaft 5101 rotate about theaxle 5009.

Referring to FIGS. 165-172, sprocket 5105 may be any type of geared ortoothed sprocket, gear, cogwheel, lever(s), or other geometry (hereaftersimply “sprocket”) mounted on the inside end of the collection shaft5101 having a configuration designed to operably engage one or moremating indexing segments 5104-5 having a camming profile arranged on theindexing ring 5104. In one embodiment, a plurality of indexing segments5104-5 is provided. Indexing segments 5104-5 each may have an undulatingcamming configuration or profile in side view which operably engages androtates the sprocket 5105. The indexing segments may each comprise aseries of alternating raised protrusions or teeth, ramps, and recessesselected in sequence and dimension to engage and actuate/rotate thesprocket arms or lugs 5105-1, thereby in turn rotating the collectionshaft 5101 as it rotates with the coulter 5100. The indexing segments5104-5 are circumferentially spaced at predetermined intervals separatedby flat areas in between on the indexing ring 5104 which do not actuateor rotate the sprocket. The camming profile segments 5104-5 may have anarcuately curved shape in plan view on the annular-shaped indexing ring.

Indexing ring 5104 has a generally planar annular body comprising acentral opening 5104-4, first major surface 5104-1, opposing secondmajor surface 5104-2 parallel to the first major surface, and aperipheral sides 5104-3 extending between the surfaces. First majorsurface 5104-1 may be plain in one embodiment. The second major surface5104-2 faces the blade 5001 when assembled and includes the indexingsegments 5104-5. In some embodiments, two or more indexing segments5104-5 may be provided. Four may be provided in the non-limitingillustrated embodiment which may be spaced circumferentially apart atuniform arc lengths. The indexing segments 5104-5 are circumferentiallyspaced apart around the indexing ring at specific discrete intervals orlocations selected to time actuation (i.e. rotation) of the collectionshaft 5101 at predetermined intervals in conjunction with rotation ofblade 5001 to collect soil samples to either open or close the samplecollection ports 5102 in the shaft. The indexing segments 5104-5 aretherefore used to precisely time and rotationally position the sprocket5105 in cooperation with the rotational position of blade 5001 tocapture or not capture soil samples based on the rotational positions ofthe blade and collection shaft 5101 (e.g. above or in soil and depth) byopening or closing the collection ports 5102, as further describedherein.

FIG. 164 depicts a side perspective view showing the profile of oneexample of an indexing segment 5104-5. FIG. 163 is cross section of theindexing segment taken from FIG. 162. In on non-limiting embodimentillustrated, the indexing segment may include a pair of arcuately spacedapart raised protrusions or teeth 5110, 5114. A recess or valley 5113 isformed between the teeth having a depth which defines a thickness T2 ofthe indexing ring 5104 (measuring between the top and bottom majorsurfaces 5104-1, 5104-2) which is less than the baseline thickness T1 ofthe flat portions of the ring without an indexing see, e.g. In oneembodiment, the valley 5113 may be separated from the leading tooth 5110by a short flat portion 5115 of the indexing ring 5104 having an arclength less than the arc length between the leading and trailing teeth5110, 5114. This defines a flat ledge or shelf 5112 at the trailing sideof leading tooth 5110 forward of the valley 5113. Valley 5113 may bedisposed on the leading side of the trailing tooth 5114 and adjoins thistooth. The trailing/leading teeth or sides are defined herein bydirectional rotation of the coulter 5100 and sprocket 5105 as thesprocket initially engages and rotates through each indexing segment5104-5. In one embodiment, the leading tooth 5110 may include aninclined ramp 5111 on the leading side to more gradually engage androtate the lugs 5105-1 of sprocket 5105. The thickness T3 of theindexing ring 5104 at each tooth 5110, 5114 measured between the apex ofthe teeth and bottom surface 5104-2 of the ring is greater than thebaseline thickness T1 of the flat portions 5115 of the ring. Othernumbers and configurations of the indexing segments 5104-5 andteeth/valleys are possible in other embodiments.

Sprocket 5105 in one non-limiting embodiment may include a plurality ofradially protruding arms or lugs 5105-1 arranged to engage the indexingsegments 5104-5 of indexing ring 5104. In this example, four lugs 5105-1are provided; however, other embodiments may have more or less lugs. Thelugs 5105-1 may be arranged in two diagonal pairs as shown which areuniformly spaced apart on the sprocket.

It will be appreciated that in other possible embodiments contemplated,the sprocket 5105 may be a convention geared sprocket with uniform teethextending a full 360 degrees and each mating indexing segment 5104-5 maya geared or tooth rack having convention teeth selected to engage theteeth of the sprocket. Other arrangement of mutually configured andengaging sprockets and indexing segments may be used in otherembodiments.

Operation of the coulter assembly 5100 for capturing and ejecting a soilsample will now be briefly described with reference to FIGS. 173A-178B.By changing the geometry of the indexer (i.e. the location and number ofthe indexing segments 5104-5 on indexing ring 5104 and theirconfiguration), the coulter assembly 5100 can be used to close or openthe collection ports 5102 on the collection shaft 5101 at any point inthe coulter blade's rotation.

FIGS. 173A-B shows the coulter assembly in a first operating positionwith the collection shaft 5101 in about the 8 o'clock position (lowerleft quadrant of blade profile). Sample collection shaft 5101 is in thefully closed position rotated so that the collection ports 5102 areclosed to the ingress of soil. The blade 5001 and shaft assembly arerotating counter-clockwise (arcuately left to right in the figure), andthe sprocket 5102 is about to contact the indexing ring 5104. Thecollection shaft 5101 is located above the surface 5003 of the ground orsoil 5002 at this point as the blade 5001 rotates through the soil (seeblade and shaft rotational direction arrows in these figures). It willbe remembered that the blade and shaft rotate relative to the indexingring 5104 which remains stationary being affixed to the frame of thewheeled sample collection vehicle.

FIGS. 174A-B show the coulter assembly in a second operating positionrotated farther downward closer to the 6 o'clock position. Samplecollection shaft 5101 is still in the closed position rotated withcollection ports 5102 closed. The collection shaft 5101, however, hasnow penetrated the surface 5003 of the ground or soil 5002 at this pointas the blade 5001 rotates through the soil. The sprocket 5102 has madeinitial engagement with one of the indexing segments 5104-5 (i.e.leading tooth 5110) to initiate rotation of collection shaft 5101.

FIGS. 175A-B show the coulter assembly in a third operating positionrotated farther downwards closer to the 6 o'clock position than before.The sprocket 5102 is further engaged with the indexing segment whichcontinues to rotate the collection shaft 5101 and further opens thesample collection ports 5102 which are still not quite open enough tocollect soil. The indexing segment 5104-5 kicks off the trailing lug ofthe sprocket in order to nose down the leading lug of the sprocket. Thecollection shaft 5101 is in a partially open position, but approximatelyless than halfway opened at this juncture.

FIGS. 176A-B show the coulter assembly in a fourth operating positionrotated farther downwards almost at the 6 o'clock position. The sprocket5102 is more fully engaged now with the indexing segment 5104-5. Theleading lug of the sprocket is pulled back by the indexing segment,which continues to rotate the collection shaft 5101 and further opensthe sample collection ports 5102 so that they are about halfway opened.This is the mid-way point of the collection shaft 5101 between its fullyclosed position and fully open position.

FIGS. 177A-B show the coulter assembly in a fifth operating positionwith collection shaft 5101 rotated farther downwards to the vertical 6o'clock position in the soil. The sprocket 5102 is further engaged withthe indexing segment 5104-5 which continues to rotate the collectionshaft 5101 to its fully open position with the outward facing collectionports 5102 now fully open to retrieve a soil sample plug or core. Theposition at which the ports open and the length of time that the vesselsremain open can be varied at any rotational position of the coulterblade 5001 and collection shaft 5101 by changing the configuration anddesign of the indexing ring 5104 with respect to the indexing features(i.e. teeth, valleys, etc.) of the index segments 5104-5, their number,and placement along the ring. It is well within the ambit of thoseskilled in the art to make such adjustment to achieve the desiredopening and closing timing of the collection ports without further undueelaboration.

FIGS. 178A-B show the coulter assembly in a sixth operating withcollection shaft 5101 now rotated upward past the 6 o'clock positioncloser towards the 3 o'clock position. The first indexing segment 5104-5has been disengaged by the sprocket 5102 as blade 5001 and collectionshaft 5101 rotates beyond the first indexing second. A second indexingsegment 5104-5 has now engaged and disengaged the sprocket 5102 causingit to further rotate such that the collection shaft 5101 is returned toits fully closed position as shown with collection ports 5102 fullyclosed again as the coulter assembly continues to roll; the processbeing very similar to the one just described to expose the collectionports. Sprocket 5102 is shown disengaged with the second indexingsegment 5104-5 and is traveling over one of the flat portions 5115 ofthe indexing ring 5104 which do not operably engage and rotate thecollection shaft 5101 to maintain its closed position.

Once the coulter assembly (e.g. blade 5001 and collection shaft 5101)has rotated to the point where the collection shaft 5101 is above thesurface of the surface of the ground or soil, the next succeedingindexing segment 5104-5 may then engage and rotate the sprocket 5105 toagain turn the collection shaft to its fully open position so thecollected soil samples (e.g. plugs or cores) can be removed by anysuitable means (e.g. via a blast of pressurized air directed at thecollection ports or insertion of a mechanical ejector such as a rod orlever through the ports as some non-limiting examples).

Slider Sample Collection Probes

FIGS. 179-185 depict an embodiment of a ground-engaging coulter assembly5200 for collecting soil samples with an onboard sample collection probein the form of linearly moveable collection sliders 5201. The collectionsliders 5201 are radially movable along an actuation axis AAperpendicular to the axis of rotation RA1 of the coulter blade 5001.Each slider operates to selectively open/close a correspondingcollection recess or port 5202 formed within a radial slot 5203 in theblade. Collection ports 5202 may extend completely through the blade5001 between its major surfaces. The sliders 5201 are actuated by astationary cam ring 5204 (e.g. analogous to cam ring 5006 previouslydescribed herein) to alternatingly open and close the collection portsas the coulter blade 5001 rotates. The ports 5102 are arranged and maybe configured to retrieve soil sample plugs or cores at the same ordifferent preselected depths as the coulter blade rolls and cuts throughthe ground. The collected cores are then ejected/extracted from thecollection ports 5202 and transferred to a collection receptacle.Coulter assembly 5200 may be mounted to the frame of or trailer pulledby an engine-powered wheeled sample collection vehicle which traversesan agricultural field (e.g. tractor, etc.) for collecting soil samples.

Coulter assembly 5200 generally comprises many of the same components ascoulter assembly 5000 previously described herein. This includes thedisc-shaped coulter blade 5001, blade hub 5004 for mounting the bladethereto, outer hub collar 5007 fixedly attached to the hub and rotatabletherewith, and annular bearing 5008. These components will not bedescribed here again and are not shown in FIGS. 179-185 for sake ofbrevity and clarity. For simplicity, the blade hub 5004, hub collar5007, and bearing 5008 are represented by dashed shaft. The presentcoulter assembly is assembled in the manner shown in the figures andfurther described below.

Collection sliders 5201 may have an elongated solid rectangular bodywith a rigid bar-like construction (best shown in FIG. 181). The sliders5201 occupy a majority, and preferably more than ¾ of the length of eachradial slot 5203 but not the entire slot to allow formation of theopenable/closeable collection ports 5202 in the outboard ends of eachradial slot. Sliders 5201 are slideably retained in each radial slot5203 by a plurality of mounting straps 5205 affixed to opposite sides(i.e. blade major surfaces 5001-1 and 5001-2) of the blade 5001. Thestraps 5205 span or bridge across and over the collection sliders 5201trapping the sliders therebetween within the radial slot 5203. Straps5205 may be fixedly attached to the coulter blade 5001 by any suitablemeans, such as without limitation tack welding, adhesives, fasteners, orother. The straps 5205 may be arranged in mating pairs directly oppositeeach other on the blade major surfaces 5001-1 and 5001-2.

The collection sliders 5201 are selectively and automatically actuatedvia a camming mechanism provided by annular cam ring 5204 and a follower5206 mounted to the inside ends of the collection sliders 5201. Eachslider 5201 is linearly and radially movable independently of each othervia configuration of the cam ring 5204. Cam ring 5204 is configured forfixed attachment to the frame of the wheeled collection vehicle such asvia mounting bracket 5010 shown in FIGS. 137 and 139. Cam ring 5204therefore remains stationary and fixed in position relative to thecoulter blade 5001 with collection sliders 5201 which rotates as theblade is pulled or pushed through the soil.

Cam ring 5204 may be similar in construction and configuration to camring 5006 and includes the same constituent portions/parts previouslydescribed herein in detail, which will not be repeated here again forthe sake of brevity. The cam track 5006-5 may be shaped similarly to camring 5006, or cam ring 5204 may have a 360 degree cam track withdifferent configuration in some embodiments. In either case, portions ofthe cam track 5006-5 are spaced by varying radial distances D1 (minimum)and D2 (maximum) from central opening 5006-4 of the cam ring 5204 toselectively slide the collection sliders 5201 radially outwards andinwards. Other locations within cam track 5006-5 may vary betweendistances D1 and D2.

In one embodiment, the follower 5206 may be formed by an annular bearing5207 mounted to the inside end of each collection sliders 5201 by anysuitable means. Bearing 5207 may be a ball bearing in one example. Inone embodiment, the follower bearing 5207 may be mounted to the slide5201 via a fastener such as a nut and bolt 5208 assembly; the latter ofwhich is passed through the bearing and a hole in the slider as shown.This allows the follower 5206 to rotate about the bolt defining afollower axis as the follower moves along the annular track in the camring 5204. The followers 5206 associated with each collection sliders5201 will travel through and circulate around the cam track 5006-5 toselectively actuate the sliders and open/close the collection ports5202.

In operation, as the coulter blade 5001 rotates, the cam track 5006-5 isconfigured to selectively open and close the collection ports 5202 atdifferent rotational positions of the blade for either collection of orpreventing collection of soil samples (this is similar to the operationof cam ring 5006 previously described herein). Each slider 5201 isindependently actuated to be fully radially extended within its radialslot 5203 as it rotates into the soil to close its collection port 5202,not allowing collection of a sample. After the blade 5001 enters thesoil, the slider 5201 embedded in the soil is drawn fully and radiallyinwards at the desired depth by interaction between the cam track 5006-5and follower 5206 (representing the portion of the track associated withdistance D1). This fully opens the collection port 5202 at the outboardend of radial slot 5203 to retrieve a soil sample. Before the collectionport 5202 rotates out of the desired depth, the slider begins to closeto retain the sample in the port. The cam ring 5204 continues to applypressure on the collection slider 5201 via the cam follower 5206 keepingthe collection soil sample packed and retained in the collection port5202. After the sample leaves the soil, the cam ring 5204 begins to openthe slider 5201 to release pressure on the sample allowing forextraction of the sample. At some point above the soil surface, the soilsample is removed pneumatically or mechanically in similar fashion tothat already described herein with respect to the piston-operatedcoulter assembly 5000. After extraction, the now empty collection port5202 is then fully re-closed by the slider 5201 via the cam ring 5204before it enters the soil again as the blade 5001 continues to rotate.When the slider 5201 again enters the soil and reaches the desiredcollection depth, the collection port 5202 will again open in the samemanner previously described to retrieve a second soil sample. It bearsnoting that this process occurs for each of the plurality of samplecollection sliders 5201 and collection ports 5202 disposed on thecoulter blade. Accordingly, a sample may be collected concurrently orsemi-concurrently by one below-grade slider 5201 and extracted fromanother above-grade slider. Any desired number of sliders may beprovided.

It will be appreciated that soil samples may be collected at varyingdepths by timing the opening/closing of the collection ports 5202through configuring the shape of the cam track 5006-5 of cam ring 5204.It is well within of those skilled in the art to provide an appropriatecam ring configuration for collecting samples at the desired depths.

The outside terminal ends 5201-1 of the collection sliders 5201 and theoutside terminal ends 5203-1 of the radial slot 5203 (collection ports5202 defines therebetween) may have a variety of configurations whichdefine the shape of the collection ports 5202. FIGS. 179-185 showstraight terminal ends of the sliders and slots forming a rectilineargeometry of the collection pockets (best shown in FIG. 182). FIG. 186shows an alternative non-rectilinear and undulating terminal end shapeof the sliders and slots having a variable geometry. This geometrycreating multiple arcuately curved and concave sub-pockets 5203-2 whichare ideally suited for collection and retention of variable soils.Sub-pockets 5203-2 may have the same or different sizes as illustrated.Other geometries may be used for collection ports 5202.

FIG. 187 shows a non-limiting example of how cam ring 5204 with camtrack 5006-5 can be configured to open or close the collection port 5202via operation of the slider 5201 in a timed manner for collecting,retaining, and removing a soil sample using coulter blade assembly 5200.This figure shows the rotational progression of a single collectionslider 5201 and port 5202 as the blade 5001 rotates through the soil andis self-explanatory. It will be appreciated that the blade 5001 willinclude a plurality of angularly/circumferentially spaced apartcollection slides as shown for example in FIG. 179.

FIG. 188 shows an alternative variation of the sample collection coulterassembly 5200 for collecting soil samples at different depths using asingle coulter blade 5001. Whereas the collection sliders 5201 andradial slots 5203 in FIGS. 179-187 each have the same length, thesliders and radial slots in coulter assembly 5230 have differentlengths. This places the collection ports 5202 at different radialdistances from the center of the coulter blade. This design thus allowscollection of samples at different depths in the soil using a singleblade 5001.

Slider Sample Collection Probe with Shielded Ports

FIGS. 189-196 depict an alternative embodiment of a ground-engagingcoulter assembly 5300 for collecting soil samples with an onboard samplecollection probe in the form of linearly moveable collection sliders5301. The coulter assembly 5300, including elongated collection sliders5301, is essentially identical to coulter assembly 5200 previouslydescribed herein above and functions in the same manner. The collectionsliders 5301 are selectively and automatically actuated via the samecamming mechanism provided by annular cam ring 5204 and followers 5206mounted to the inside ends of the collection sliders 5301. These samecomponents and their operation for collecting soil samples will not berepeated here for sake of brevity.

By contrast, a difference in the present design variation embodied incoulter assembly 5300 is that each slider 5301 further includes aplurality of outwards facing collection ports 5302 spaced radially apartalong the length of the slider for capturing soil samples at differentdepths. Collection ports 5302 may preferably be through openingspenetrating both opposing sides (e.g. front and back) of the slider toallow the extracted soil samples to be ejected mechanically orpneumatically from ports for chemical processing/analysis. Collectionports 5302 may be round holes or apertures in one embodiment.

Each collection port 5302 in slider 5301 has an associated pair ofmounting straps 5205 affixed to opposite sides (i.e. blade majorsurfaces 5001-1 and 5001-2) of the blade 5001; the same as coulterassembly 5200. As previously described herein, the straps 5205 span orbridge across and over the collection sliders 5201 trapping the sliderstherebetween within the radial slots 5203. The straps 5201 rotate withcoulter blade 5001 and remains fixed relative thereto. The sliders 5301operate in the same manner as sliders 5201 previously described herein,and therefore reciprocate in a radial linear direction beneath thestraps.

The straps 5205 in coulter assembly 5300 however act as shields whichalternatingly expose or conceal the collection ports 5302 beneath themas the blade 5001 rotates through the soil. As shown in FIGS. 190-192,the sliders 5301 are moveable between a first radial position in whichthe collection ports 5302 are retracted and covered by the straps 5205to prevent collection of soil samples/cores (see, e.g. slider at 3o'clock position), and a second radial position in which the collectionports emerge from beneath the straps and are exposed (see, e.g. sliderat 6 o'clock position) for either capturing a soil sample if exposedbelow grade, or extracting a collected sample if exposed above grade.

In operation, as the coulter blade 5001 rotates, each slider 5301linearly reciprocates within its radial slot 5203 cause by interactionwith the stationary camming mechanism (i.e. cam ring 5204 and followers5206 on each slider). This linear motion alternatingly exposes orconceals the collection ports 5302 as shown in FIG. 190 while the bladerotates (note open ports at 6 o'clock position and closed ports at 9 and10 o'clock positions). FIGS. 195 and 196 also shows ports 5302 in theclosed and open positions, respectively.

Coulter assembly 5300 generally comprises many of the same components ascoulter assembly 5000 previously described herein. This includes thedisc-shaped coulter blade 5001, blade hub 5004 for mounting the bladethereto, outer hub collar 5007 fixedly attached to the hub and rotatabletherewith, and annular bearing 5008. These components will not bedescribed again here again and are not shown in FIGS. 189-196 for sakeof brevity and clarity. For simplicity, the blade hub 5004, hub collar5007, and bearing 5008 are represented by dashed shaft. The presentcoulter assembly is assembled in the manner shown in the figures.

Rotatable Spindle Collection Probe

FIGS. 197-206 depict an embodiment of a ground-engaging coulter assembly5400 for collecting soil samples with an onboard sample collectionprobe. The collection probe may comprise a tubular assembly comprising arotatable inner collection spindle 5401 enclosed inside a hollow outershield tube 5403 fixedly mounted to the coulter blade 5001 and rotatabletherewith. A plurality of angularly spaced apart pairs of collectionspindles and shield tubes may be provided on coulter blade 5001. Eachcollection spindle 5401 rotates about a radial axis of rotation Rcrelative to the coulter blade 5001 of the assembly, and includes one ormore openable/closeable collection ports 5402 actuated by sprocketmechanism 5103 cam ring 5104 previously described herein toalternatingly open and close the collection ports, as further describedherein. The ports 5402 are arranged to retrieve soil sample plugs orcores at different preselected depths as the coulter blade rolls andcuts through the ground. The cores are then ejected/extracted from thecollection spindle 5401 and transferred to a collection receptacle.Coulter assembly 5400 may be mounted to the frame of or implement pulledby an engine-powered wheeled sample collection vehicle which traversesan agricultural field (e.g. tractor, etc.) for collecting soil samples.

Coulter assembly 5400 generally comprises many of the same components ascoulter assembly 5000 previously described herein. This includes thedisc-shaped body or blade 5001, blade hub 5004 for mounting the bladethereto, outer hub collar 5007 fixedly attached to the hub and rotatabletherewith, and annular bearing 5008. These components will not bedescribed again here for sake of brevity. The present coulter assemblyis assembled in the manner shown in the figures and further describedbelow.

Collection spindle 5401 may have an elongated solid cylindrical bodyincluding a plurality of laterally open collection ports 5402 spacedaxially apart along its length. Collection ports 5402 may be throughports open from two opposing sides of the spindle 5401 as shown. Theremaining two sides of the shaft are solid and closed. Ports 5402 may bein the form of round through holes extending transversely to rotationalaxis Rc in the illustrated embodiment; however other shaped portsincluding elongated ports in the form of slots may be provided. Anynumber of collection ports 5402 may be provided depending on the numberand depths of soil samples desired.

The outer shield tubes 5403 each comprise a plurality of spaced apartwindows 5404 formed along the length of the tubes to provide access tothe collection ports 5402 in spindle 5401. Each window is thereforelocated on shield tube 5403 for alignment with a mating collection port5402 in spindle 5401 inside the tube. The collection ports and windows5404 therefore have the same spacing along the lengths of the shieldtubes 5403 and spindles 5401. This forms pairs of collection ports andwindows which are concentrically aligned. Windows 5404 may becomplementary configured to collection ports 5402. In the non-limitingillustrated embodiment, the windows 5404 and collection ports 5402 eachhave a round shape. In other embodiments, the windows 5404 andcollection ports 5402 may have other shapes such as mating pairs ofelongated slots. Shield tube windows 5404 preferably are throughopenings extending through two opposing exposed sides of the shield tube5403 as shown. The remaining two sides of the shaft are solid andclosed.

The shield tubes 5403 are disposed in each elongated radial slot 5203 inblade 5001. The opposing arcuately shaped circumferential walls of thetubes 5403 protrude outwards above each of the major surfaces 5001-1,5001-2 of the blade to better capture soil. Each shield tube 5403 isrigidly affixed or mounted to blade 5001 in the slots 5203 such as viawelding or other suitable fixation means. The shield tubes 5403therefore remain stationary relative to the blade 5001 as it rotates.The collection spindles 5401 mounted inside the shield tubes 5403,however, are rotatable relative to its tube about each spindle'sradially-oriented axis of rotation Rc defined by the radial centerlineof the an axis blade 5001. The spindles 5401 thus rotate independentlyrelative to the blade inside the shield tubes 5403.

Collection spindles 5401 are rotatably supported inside shield tubes5403 by a plurality of radially spaced apart bearings 5405, as bestshown in FIGS. 204-206. Bearings 5405 may have an annular circular shapeand may be formed by diametrically enlarged portions of the spindlerelative to other portions of the spindle between the bearings as shown.The bearings 5405 may be formed as integral unitary structural parts ofa monolithic spindle body in one embodiment. In one arrangement, thecollection ports 5402 are formed through the bearings to provide amaximum volume in each port for capturing a soil sample. In otherembodiments contemplated, collection ports 5402 may be formed in thediametrically narrower portions of spindle 5401 between bearings 5405.Each collection port 5402 may be sealed off within shield tube 5403 by apair of annular seals such as an O-ring mounted in circumferentialgrooves of the bearings 5405 on each side of the ports.

Collection spindle 5401 is rotatable between an open rotational positionin which the collection ports 5102 are each concentrically aligned withits mating shield tube window 5404 and open for capturing soil (see,e.g. FIGS. 204 and 206), and a closed rotational position in which thecollection ports are each rotated away from and misaligned with itsmating tube window and closed to preclude soil from entering thecollection ports (see, e.g. FIG. 205) In the open position, theprotrusion of the open windows of the shield tubes 5403 above the majorsurfaces 5001-2, 5001-2 facilitate entry of the soil sample into thecollection ports 5102. Further, in the open position, the collectionports 5402 of spindle 5401 and shield tube windows 5404 both faceoutwards away from the slot 5203 and are exposed for capturing soil foreither side of the dually open ports and windows. In the closed positionwhen a soil sample is not desired, the collection ports of spindle 5401face inwards and laterally towards the opposing sides of slot 5203 andthe plane of the blade 5001. This exposes the solid sides of thecollection spindle to the shield tube windows 5404 which precludes soilfrom entering the collection ports 5402.

To actuate and rotate the collection spindle 5401 between its open andclosed positions, a rotary mechanism such as without limitation sprocketmechanism 5103 may be used to rotate the collection spindle forselectively collecting soil samples at predetermined depths. Sprocketmechanism 5103 already described above with respect to coulter probeassembly 5100 includes the annular timing or indexing ring 5104 andsprocket 5105. In the present design, sprocket 5105 may instead befixedly attached to the inside end of the collection spindle 5401 in asimilar manner to mounting the sprocket to collection shaft 5101previously described herein. Indexing ring 5104 is fixedly mounted tothe frame of the engine-powered wheeled sampling vehicle via bracket5101 as previously described herein (similarly to cam ring 5006). Theindexing ring 5104 thus remains stationary as the blade 5001 andcollection shaft 5101 rotate about the axle 5009.

As the coulter blade 5400 rotates, the collection ports 5402alternatingly open and close to collect or preclude collection of soilsamples in the same general manner previously described herein withrespect to coulter blade assembly 5100.

Piston-Operated Sample Collection Probe with Flexible Cam Ring

FIGS. 207-216 depict a variation of the piston-operated coulter assembly5000 of FIGS. 137-152 for collecting soil samples. The same pistonmechanism 5020 comprising cam follower 5021 fixedly disposed on theinside end 5023-1 of piston rod 5023 which operably engages the camtrack 5006-5A is provided in the present embodiment. However, therigidly structured annular cam ring 5006 of coulter assembly 5000 ismodified and replaced in the present coulter assembly 5500 by aresiliently deformable cam ring 5506. At least a part of cam ring 5506,or in some embodiments the entire cam ring 5506 may be formed of anelastically deformable and resilient material having an elastic memory.

One potential shortcoming of a rigidly structured coulter cam ring isthat, in certain situations, it may be structurally unforgiving of anysubstantial mechanical resistance or temporary jams in the pistonmechanism as it reciprocates when plowing through the soil to collect asample. Debris or rocks/stones in the soil may create such resistance orjams. In some circumstances if the jam is severe enough, this could leadto potential failure in the piston mechanism of the coulter assembly.For example, if a jam would occur, the cam ring could exert enough forceon the cam follower 5021 to damage some part of the jammed mechanism(e.g. piston rod 5023, collection cylinder 5022, bushing 5025, etc.),thereby compromising the coulter's ability to collect soil samples.

To prevent such an overstressing event on the piston mechanism, adeformable cam ring 5506 is provided in the present embodiment. The camring 5506 may be made of a durable, semi-rigid yet elastic material orcombination of materials, that would enable the cam ring to partiallycompress and yield in the event of any mechanical issue or externalforces that prevents the cam follower 5021 from properly rolling/slidingand changing position in the cam track 5006-5 as the coulter blade 5001rotates. Optimally, the widest or thickest areas of the cam ring 5506adjoining the cam track preferably should be structured to be especiallycompliant/flexible as those portions of the track would be the areasused to displace the cam follower roller the largest radial distancesresulting in generation of the greatest radially-acting forces.

FIG. 207 depicts a force-resistant coulter assembly 5500 having acamming mechanism with elastically deformable cam ring 5506. Coulterassembly 5500 may be mounted to the frame of or implement pulled by anengine-powered wheeled sample collection vehicle which traverses anagricultural field (e.g. tractor, etc.) for collecting soil samples in asimilar manner to the prior coulter assemblies.

Referring to FIGS. 207-216, coulter assembly 5500 generally comprisesmany of the same components as coulter assembly 5000 previouslydescribed herein. This includes the disc-shaped body or blade 5001,blade hub 5004 for mounting the blade thereto, outer hub collar 5007fixedly attached to the hub and rotatable therewith, and annular bearing5008. These components will not be described again here for sake ofbrevity. The present coulter assembly is assembled in the manner shownin the figures and further described below. Piston mechanism 5020 may besame as previously described herein and operates for collecting soilsamples in the same manner. During the radially reciprocating operationof the piston rod 5023 as the blade 5001 rotates, the outside end 5023-2of the piston rod selectively opens or closes the outside soilcollection end 5022-2 of the collection cylinder 5022 and a pair oftransverse holes 5022-1 therein. The cylinder outside end is spacedinward from the outer end 5024-2 of radial slot 5024 to form an open gapor recess 5024-3 in blade 5001 to allow soil to enter or be ejected fromthe outside end 5023-2 of cylinder 5022 as previously described herein.

Deformable cam ring 5506 may be configured similarly to rigid cam ring5006 previously described herein. Cam ring 5506 has an annular bodydefining a central opening 5525 for receiving the blade hub assembly andcircumferentially continuous cam track 5006-5 which extends a full 360degrees around the ring. Similar to cam ring 5006, the deformable camring 5506 is configured for fixed attachment to the frame of the wheeledcollection vehicle such as via mounting bracket 5010. Cam ring 5506therefore remains stationary and fixed in position relative to the frameand the blade-hub-collar assembly as the coulter blade 5001 is pulledthrough the soil and rotates.

The deformable cam ring 5506 may be an assembly of discrete annularouter and inner guide ring members 5506-1 and 5506-2 affixed in a rigidmanner to a common annular backing plate 5501 for support. The backingplate 5501 may have a substantially planar body and may have a rigidstructure in one embodiment. The ring members 5506-1, 5506-2 are fixedlymounted to and spaced radially apart on backing plate 5501 to define theannular opening for the cam track 5006-5. Backing plate 5501 forms aclosed bottom wall of the cam track 5006-5 opposite the outwardly opentop end of the cam track which receives the cam follower 5021 therein toengage the track. In some embodiments, each ring member 5506-1, 5506-2may be mounted on its own circular annular mounting flange 5521 and5522, which in turn are each mounted to the common backing plate 5501.The mounting flanges may each have a generally L-shaped transverse crosssection in one embodiment. Flanges 5521, 5522 each define a firstmounting section 5521-2, 5522-2 configured for mounting to backing plate5501 and a second guide ring support section 5521-1, 5522-1 for securingthe outer and inner guide ring members 5506-1, 5506-2 thereto. The guidering support sections may be oriented perpendicularly to the mountingsections in one embodiment. The mounting sections 5521-2, 5522-2 mayinclude a plurality of mounting holes for fixedly attaching the mountingflanges 5521, 5522 to the backing plate 5501 in radially spaced apartrelationship. Other mounting arrangements and methods of mounting arepossible, such as for example industrial adhesives, welding, riveting,etc. The backing plate 5501 and mounting flanges 5521, 5522 can beformed of any suitable rigid metallic or non-metallic material. In oneembodiment, these components are preferably made of a suitable metalsuch as steel or aluminum as some non-limiting examples.

The outer and inner guide ring members 5506-1, 5506-2 are each fixedlymounted in a cantilevered manner to the guide ring support sections5521-1, 5522-1 of the mounting flanges 5521, 5522. In one embodiment,the guide ring members are overmolded onto the mounting flanges;however, other methods may be used for fixedly securing the guide ringmembers thereto such as industrial adhesives. The guide ring members5506-1, 5506-2 are each spaced apart from the mounting sections 5521-2,5522-2 of the mounting flanges. This forms annular air gaps 5510, 5511therebetween which communicate with the open cam track 5006-5.Advantageously, the air gaps provide freedom of movement and impartmaximum flexibility to the outer and inner guide ring members 5506-1,5506-2 which are unencumbered by the rigid attachment of the mountingflanges 5521, 5522 to the backing plate 5501.

It bears noting that although the annular mounting flanges 5521, 5222may be circular in shape (e.g. in top plan view) with a generallyuniform measured between the inner and outer circumferential peripheraledges of the mounting sections 5521-2, 5522-2 of each flange, the guidering members 5506-1, 5506-2 will have corresponding variable widths atdifferent portions and therefore are not perfectly circularly in shape(in top plan view). This is seen for example in FIG. 214 noting innerperipheral edges of mounting section 5522-2 (extending beyond portionsof guide ring member 5506-2) and 5521-2 (visible through slots 5505 inguide ring member 5506-1). The primary reason for this difference isthat the portions of the guide ring members 5506-1, 5506-2 width willchange depending on the desired variable configuration of the cam track5006-5 necessary to actuate the piston mechanism 5020 at the desiredrotational timing interval of the coulter blade assembly 5500 forcollecting soil sample.

Backing plate 5501 of the cam ring 5506 assembly is configured for rigidmounting to mounting bracket 5010 (FIG. 140) of the coulter assembly5500, such as via a plurality of mounting holes as shown which receivethreaded fasteners. Other methods of fixedly mounting the cam ring base5501 to mounting bracket 5010 may be used, such as riveting, welding, orindustrial adhesives as some non-limiting examples. The cam track 5006-5may have the same or different shape/configuration as cam ring 5006depending on the type of action to be imparted to piston mechanism 5020and timing of the opening/closing of the sample collection cylinder 5022for capturing or extracting a soil sample.

The outer and inner guide ring members 5506-1, 5506-2 may be formed ofthe same or different materials. In certain embodiments, one or both ofthe ring members may be formed at least in part or completely of aresiliently deformable material with elastic memory. In someembodiments, one of the guide ring members 5506-1, 5506-2 may be formedof a rigid material and the other one may be formed of a deformablematerial. Accordingly, numerous variations are possible to accommodatedifferent situations or design goals.

Guide ring members 5506-1, 5506-2 of cam ring 5506 may be made of anysuitable material. For example, one or both of the guide ring membersmay formed of a semi-rigid or semi-stiff (i.e. relatively hard), yetdeformable polymeric material such as polyurethane, or a combination ofmaterials to achieve the desired mechanical/structural properties. Thepolyurethane ring members are structured to be at least partiallydeformable for engaging cam follower 5021 and deforming under radiallyacting forces generated along axis AA by the piston mechanism 5020 whenencountering a jammed or other abnormal operating condition of thecoulter blade when collecting a sample.

The deformable base material such as polyurethane or another materialused to form outer and inner guide ring members 5506-1, 5506-2 may eachhaving the same or different hardnesses. A suitable durometer hardnessmaterial may be used. It is well within the ambit of those skilled inthe art to select suitable durometer hardnesses for the ring membermaterial.

In some embodiment, the deformable outer and inner guide ring members5506-1, 5506-2 may be configured to include one or more arrays ofdeformation-enabling openings 5520 designed to facilitate theflexibility and deformability of the cam ring 5506 under applied radialloads produced by the piston mechanism 5020. In some embodiments, theseopenings 5520 may transversely extend at least partially through thering members between one major side and the opposite parallel majorside. In a preferred but non-limiting embodiment, the openings 5520extending completely through the guide ring members 5506-1, 5506-2parallel to rotational axis RA1 of the coulter blade assembly 5500 tomaximize flexibility and deformability under applied compressiveloading/forces.

The outer circumferential sidewall 5504 of the outer guide ring member5506-1 and inner circumferential sidewall 5509 of inner guide ringmember 5506-2 may be solid in some embodiments, and they may be rigid orflexible. The opposite inner circumferential sidewall 5512 of outerguide ring member 5506-1 and outer circumferential sidewall 5513 ofinner guide ring member 5506-2 may similarly be solid in someembodiments, and they may be rigid or flexible.

The material removed by the forgoing deformation-enabling openings 5520provide controlled weakening of the guide ring members 5506-1, 5506-2 inthe radial direction parallel to radial actuation axis AA. The materialreduction in the guide ring members increase flexibility in the radialdirection, thereby allowing the ring member material to compress moreeasily under radial acting forces imparted by the piston mechanism 5020during a jam or other abnormal operating condition. These throughopenings 5520 (or other topographical features such as blind slots,dimples, etc.) may have any suitable shape or geometry, such as roundholes, obround holes, polygonal or non-polygonal holes or slots (e.g.honeycombs), or other shapes. Some non-limiting examples of suitableopenings 5520 are described below.

In one embodiment, one or both of the outer and inner guide ring members5506-1, 5506-2 may include a plurality of elongated and obliquely angledradial through slots 5505. In the illustrated embodiment, slots 5505 areprovided in only the outer ring member 5506-1 but they can be used inboth or just the inner guide ring member 5506-2 may have the slots.Slots 5505 may be arcuately curved in one embodiment and extendcompletely through the opposing major sides 5502 and 5503 of the outerring guide member 5506-1 in the axial direction of rotational axis RA1.Slots 5505 are radially oriented and arrayed at least partially aroundthe circumference and the central opening 5506-4 of the cam ring 5506.The slots 5505 allow outer ring member 5506-1 to deform and compressmore easily when radially engaged by the cam follower 5021. The throughslots 5505 extend transversely and obliquely with respect to the outerring member 5506-1 and the rotational direction vector Vd of the coulterblade 5001 (albeit the cam ring 5506 remains stationary relative to thecoulter blade 5001). Accordingly, the leading edge of each slot 5505with respect to the rotational direction vector Vd of the wheel isproximate to the inside annular edge of the ring member 5506-1 whereasthe trailing edge is proximate to the outside annular edge.

In one embodiment, the through slots 5505 may be provided primarily inonly the widest/thickest portions of outer ring member 5505-1 toincrease flexibility and facilitate deformation of these areas wheregreater deformation may be needed than adjoining narrower/thinnerportions. In other possible embodiments, the entire outer ring membermay include one or more slots 5505. The slots 5505 may have the same ordifferent shape and/or size.

In some embodiments the deformation-enabling openings 5520 may comprisean array of round bore holes 5526 each having a circular cross-sectionalshape. Bore holes 5526 are shown for example formed in the inner guidering member 5506-2, recognizing that in other embodiments holes 5526 maybe formed in the outer ring member 5506-1 or both. The bore holes 5526may extend completely through the ring member between the opposing majorsides 5507 and 5508. Bore holes 5526 in the array may have any suitablediameter and pitch spacing between the holes. In one embodiment, theholes 5526 may be closely spaced apart with a pitch spacing measuredbetween the centerlines of the adjacent holes being less than 5 holediameters, or preferably less than 3 hole diameters. Any suitablepattern of holes 5526 may be provided. In one embodiment, the holes 5526may be arranged in concentric rings of holes extending at leastpartially around the circumference of the inner guide ring member5506-2. The bore holes 5526 may be disposed substantially in only thethickest/widest portions of the inner guide ring member to addflexibility to those areas where more deformation may be needed. Thenarrower portions of the guide ring member 5506-2 may have fewer or noholes to increase rigidity.

It bears noting that a large variety of possible geometries and patternsof arrays of the deformation-enabling openings 5520 may be used. Suchpatterns could take the shape of isotropic patterns (i.e. same in allorientations/directions such as bore holes 5526), or directionallybiased patterns (e.g. swept slots 5505). The opening geometries andpatterns may be used to create a linear or non-linear compression forceresponse profile. The opening geometries/patterns may be varied aroundthe guide ring members 5506-1, 5506-2 to create customized areas ofspecific stiffness or flexibility. Accordingly, a guide ring member maybe rigidly structured in some areas (e.g. narrow areas), yet moredeformable in other areas (e.g. wide areas). Whatever the specificgeometry and patterns selected for deformation-enabling openings 5520,the openings are preferably designed to provide the necessary rigidityto properly actuation and position the piston mechanism 5020 mechanismand the flexibility to prevent overstressing the parts of the pistonmechanism in the event of jams to avoid permanent damage to themechanism.

Accordingly, it is important to note here that different geometries andpatterns of deformation-enabling openings 5520 will have differentresponses to compression. Therefore, round holes (e.g. bore hole 5526arrays might be used in one region or area of the guide ring members5506-1, 5506-2 while elongated slots (e.g. through slots 5505) may beused in another region or area of each guide ring member to achieve adifferent “spring” response from the material. Some geometries may actdifferently to different external loading scenarios or directions ofapplied force by the cam follower 5021. For such foregoingconstructions, the collective whole structure of the guide ring members5506-1, 5506-2 would then be considered to exhibit a “non-lineareffective spring rate.”

In operation, the piston mechanism 5020 of the coulter assembly 5500will operate in the same manner as embodied in coulter assembly 5000 forcollecting soil sample. Reference is made to FIG. 148 showing the pistonmechanism 5020 which is the same in the coulter blade assembly 5500.However, if the piston rod 5023 becomes jammed for some reason incoulter blade assembly 5500 with the deformable cam ring 5506, the camfollower 5021 will impart a radially acting force on either the outer orinner guide ring members 5506-1, 5506-2 as the follower circulatesthrough the cam track 5006-5. The ring member acted upon by the camfollower will depend on which portion of the cam track 5006-5 that thecam follower happens to be moving through at the time of the jam. Thecam follower 5021 will therefore engage and compress the inner or outerguide ring member in a radial direction. The deformation-enablingopenings 5520 will allow the ring members to elastically deform morereadily to absorb the impact forces without damaging the pistonmechanism. This allows time for the jam to clear itself if possible.

It will be appreciated that numerous variations of the coulter assembly5500 with deformable cam ring 5506 are possible within the scope of thepresent disclosure. Furthermore, the deformable cam ring may be usedwith any of the coulter assemblies discloses herein which utilize a camring to actuate the collection sliders or similar collection devices.

Slider Sample Collection Probe with Laminated Blade Assembly

FIGS. 217-251B depict an embodiment of a ground-engaging coulterassembly 5600 with laminated blade assembly 5601 for collecting soilsamples. Blade assembly 5601 has a disk shape like all other coulterblades discloses herein and comprises one or more internally mountedsample collection probe in the form of linearly and radially moveablecollection sliders 5620. Sliders 5620 may be similar in general designprinciple and basic operation to sliders 5201 previously describedherein (see, e.g. FIG. 179). By contrast to sliders 5201, however, noexternal mounting hardware such as straps 5205 are used in the presentlaminated blade embodiment to attach the sliders to the blade. Instead,each of the present sliders 5630 are captively mounted and at leastpartially embedded inside laminated blade assembly 5601 between firstand second half-sections 5601-1, 5601-2 of the blade in a sandwich-typecomposite construction. Advantageously, this eliminates externalmounting hardware to retain the sliders 5620 in the blade assembly,which may be susceptible to damage by rocks or debris when the bladeassembly plows through the soil to collect samples.

Each half-section 5601-1 of blade assembly 5601 may be a configured as amirror image of the other half-section 5601-2 having identical features,as further described herein. In other possible embodiment, there may bedifferences. The two half-sections may be permanently laminated orjoined together by any suitable method, including for example welding,industrial adhesives, rivets, or other permanent type mechanical joiningmethods. In one embodiment, the annular outer peripheral edges of thedisk half-sections 5601-1, 5601-2 may be welded together and thenmachined to form an acutely angled wedge-shaped edge profile to improvepenetration through the soil. In yet other embodiments, thetwo-half-sections may be detachably joined together via a suitablenon-permanent type joining method such as fasteners or others.

The collection sliders 5630 are radially movable along an actuation axisAA perpendicular to the axis of rotation RA1 of the coulter blade 5001.Each slider operates to selectively open/close a correspondingcollection recess or port 5602 formed within a radial slot 5603 in theblade. Slots 5603 and collection ports 5602 may extend completelythrough the laminated blade assembly 5601 between its exterior majorsurfaces. The sliders 5630 are actuated by a stationary cam ring whichmay be any of the cam rings 5006, 5204, or 5506 (previously describedherein) to alternatingly open and close the collection ports 5602 as thecoulter blade assembly 5601 rotates. The ports 5602 are arranged and maybe configured to retrieve soil sample plugs or cores at the same ordifferent preselected depths as the coulter blade rolls and cuts throughthe ground. The collected cores are then ejected/extracted from thecollection ports 5602 and transferred to a collection receptacle.Coulter assembly 5600 may be mounted to the frame of or trailer pulledby an engine-powered wheeled sample collection vehicle which traversesan agricultural field (e.g. tractor, etc.) for collecting soil samples.

Coulter assembly 5600 generally comprises many of the same components ascoulter assembly 5000 previously described herein. This includes thedisc-shaped coulter blade 5001, blade hub 5004 for mounting the bladethereto, outer hub collar 5007 fixedly attached to the hub and rotatabletherewith, and annular bearing 5008. These components will not bedescribed here again and are not shown in FIGS. 217-251B for sake ofbrevity and clarity. The present coulter assembly is assembled in themanner shown in the figures and further described below.

Laminated blade assembly 5601 and mounting of the sliders 5630 will nowbe further described. Half-section 5601-1 of laminated blade assembly5601 has a disk-shaped body including an interior major surface 5610 andopposing parallel exterior major surface 5611 facing outwards.Similarly, half-section 5601-2 has a disk-shaped body including interiormajor surface 5612 and opposing parallel exterior major surface 5613facing outwards in an opposite direction to exterior major surface 5611(see, e.g. exploded views of FIGS. 219 and 220). When joined together,the sliders 5630 are trapped between the two half-sections 5601-1,5601-2.

Four possible examples of collection sliders 5630 are disclosed hereinwhich may be used with the laminated blade assembly 5601. This includessliders 5630-1, 5630-2, 5630-3, and 5630-4 each having a differentconfiguration. One common feature is that each of the collection sliders5630 is slideably mounted in a complementary configured radial slot 5603formed in the laminated blade assembly 5601 such that only portions ofeach slider are exposed and visible, as described below.

Referring generally to FIGS. 226-251B, each of the collection sliders5630-1 to 5630-4 may have an elongated solid body with a generally rigidbar-like or rod-like overall construction. The sliders occupy amajority, and preferably more than ¾ of the length of each respectiveradial slot 5603 but not the entire slot to allow formation of theopenable/closeable collection ports 5602 in the outboard ends of eachradial slot. Each slider has common features including a cylindricallyshaped cam follower 5021 (previously described herein) on an inside endwhich engages cam track 5006-5 of the cam ring to selectively actuate atpredetermined time intervals based on rotation of the laminated bladeassembly 5601. Each slider 5630-1 to 5630-4 is further generallyT-shaped at its inside end which includes the cam follower 5021. Theopposite outside ends of the sliders may have different shapes. Thesliders and their corresponding radial slots 5603 are mutuallyconfigured to cooperate and form an interlocked arrangement whichretains each slider internally within in the laminated blade assembly5601 in a captive manner without reliance on externally mountedhardware. Portions of the sliders however may be exposed after mountingto the blade assembly as seen in the figures. Since each collectionslider 5630-1 to 5630-4 and its corresponding radial slots are shapeddifferently, they are described separately below.

FIGS. 227, 230, 236, 237, 242, 246A-B, and 250A-B show collection slider5630-1. Slider 5630-1 includes cylindrical cam follower 5021 at itsinside end, a cylindrical soil collection boss 5631 at its outside end,and an elongated operating rod 5636 with extending therebetween.Operating rod 5636 may be cylindrical having a circular transverse crosssection in one embodiment; however, other embodiments may utilize arectilinear cross-sectional shape (e.g. square or rectangular) or otherpolygonal shape (e.g. hexagonal). The cam follower 5021 and collectionboss 5631 are enlarged structures each having larger diameters thanoperating rod 5636. The follower and boss are perpendicularly orientedto the length of the operating rod as shown. A central portion of radialslot 5603 has a circular cross-sectional shape and is disposed entirelybetween the exterior major surfaces 5610, 5613 of the laminated bladeassembly 5601. This forms a concealed radially-extending circular bore5633 which slideably receives the operating rod 5636 therethrough.Elongated bore 5633 extends between and is in communication with a pairof open oblong windows 5632 formed through the blade assembly at eachend of the bore. Each half-section 5601-1, 5601-2 of the laminated bladeassembly 5601 has a semi-circular concave recess which forms one-half ofthe complete circular bore 5633 when the two half-sections 5601-1,5602-2 of the blade assembly are joined together (see, e.g. FIG. 242).The cam follower 5021 and collection boss 5631 are each received in oneof the windows 5632 and slideable therein between the ends of the windowwhen actuated by the cam ring. The windows 5632 may be oval shaped inone embodiment and oriented with their lengths arranged parallel toactuation axis AA defined by the radial slot. The cam follower 5021 hasa length (measured between its flat ends) that is greater than thethickness of the laminated blade assembly 5601 (measured between itsexterior major surfaces 5610 and 5613) such that the follower protrudesabove the exterior surfaces as shown. Conversely, the cylindricalcollection boss 5631 may have a length (measured between its flat ends)which is equal to or less than thickness of the laminated blade assembly5601 such that the boss does not protrude above the exterior majorsurfaces. In other possible embodiments, the boss may protrude above theblade exterior major surfaces to help guide soil samples into thecollection ports 5602. It bears noting that the relatively slender rod5636 in comparison to the cam follower and collection bossadvantageously reduces weight, friction with soil, and allows the rod tobe easily concealed and protected beneath the exterior of the laminatedblade assembly 5601.

FIGS. 227, 231, 238, 239, 243, and 2476A-B, and 251A-B show collectionslider 5630-2. Slider 5630-1 similarly includes cylindrical cam follower5021 at its inside end, a cylindrical soil collection boss 5631 at itsoutside end, and an elongated operating strap 5634 with rectangulartransverse cross section extending therebetween. A central portion ofradial slot 5603 has a rectangular cross-sectional shape and is disposedentirely between the exterior major surfaces 5610, 5613 of the laminatedblade assembly 5601. This forms a concealed radially-extendingrectangular passage 5635 which slideably receives the operating strap5634 therethrough. Elongated radial passage 5635 extends between and isin communication with a pair of open oblong windows 5632 formed throughthe blade assembly at each end of the passage. Each half-section 5601-1,5601-2 of the laminated blade assembly 5601 has a partial rectangularrecess which forms one-half of the complete rectangular passage 5635when the two half-sections 5601-1, 5602-2 of the blade assembly arejoined together (see, e.g. FIG. 243). The cam follower 5021 andcollection boss 5631 are each received in one of the windows 5632 andslideable therein between the ends of the window when actuated by thecam ring. The windows 5632 may be oval shaped in one embodiment and areoriented with their length parallel to actuation axis AA defined by theradial slot. It bears noting that the relatively slender/thin operatingstrap 5634 in comparison to the cam follower and collection bossadvantageously reduces weight and allows the strap to be easilyconcealed and protected beneath the exterior of the laminated bladeassembly 5601.

FIGS. 226, 228, 234, 235, 241, 245A-B, and 249A-B show collection slider5630-3. Slider 5630-3 has a generally rectangular body in transversecross section with cylindrical cam follower 5021 at its inside end. Theoutside soil collection end creates the openable/closeable soilcollection port 5602 at the peripheral portion of the blade assembly5601. Slider 5630-3 includes a pair of radially-extending and opposingguide flanges 5637 protruding outwards from each side of the slider bodyin opposite directions. Guide flanges 5637 are each slideably receivedin a mating complementary configured and radially-extending guidechannel 5638 formed in opposing sides of radial slot 5603 (see, e.g.FIG. 241). Channels 5638 are inwardly open towards radial slot 5603. Theopposing outer major surfaces of the rectangular collection slider5630-3 are exposed and visible in radial slot 5603 when mounted to theblade assembly 5601. This contrasts to the concealed portions of sliders5630-1 and 5630-2 described above. Each half-section 5601-1, 5601-2 ofthe laminated blade assembly 5601 has a perpendicular stepped shoulderwhich forms one-half of the complete guide channel 5638 when the twohalf-sections 5601-1, 5602-2 of the blade assembly are joined together(see, e.g. FIG. 241). The guide flanges 5637 are trapped within thechannels 5638 when the half-sections 5601-1 and 5601-2 are joinedtogether, thereby captively retaining the slider 5630-3 in the laminatedblade assembly without the need for external mounting hardware.

FIGS. 226, 229, 232, 233, 240, 244A-B, and 248A-B show collection slider5630-4. Slider 5630-4 has a generally rectangular body in transversecross section with cylindrical cam follower 5021 at its inside end. Theoutside soil collection end creates the openable/closeable soilcollection port 5602 at the peripheral portion of the blade assembly5601. Slider 5630-4 includes a pair of radially-extending and opposingV-shaped guide protrusions 5639 extending outwards from each side of theslider body in opposite directions. The guide protrusions 5639 defineupper and lower opposing angled guide surfaces which form an acute angletherebetween. Guide protrusions 5639 are each slideably received in amating complementary configured and radially-extending V-shaped guiderecess 5640 formed in opposing sides of radial slot 5603 (see, e.g. FIG.240). Recesses 5640 are inwardly open towards radial slot 5603. Theopposing outer major surfaces of the rectangular collection slider5630-3 are exposed and visible in radial slot 5603 when mounted to theblade assembly 5601. This contrasts to the concealed portions of sliders5630-1 and 5630-2 described above. Each half-section 5601-1, 5601-2 ofthe laminated blade assembly 5601 has an angled chamfered surface whichforms one-half of the complete guide recess 5640 when the twohalf-sections 5601-1, 5602-2 of the blade assembly are joined together(see, e.g. FIG. 240). The guide protrusions 5639 are trapped within therecesses 5640 when the half-sections 5601-1 and 5601-2 are joinedtogether, thereby captively retaining the slider 5630-4 in the laminatedblade assembly without the need for external mounting hardware.

Soil Sampling Implements and Equipment

FIGS. 252-255 illustrate non-limiting examples of various implementsconfigured to perform soil sampling and analysis, and the placement ofthe sample preparation sub-system 3002 and the chemical analysissub-system 3003. FIG. 252 illustrates a planter 10 having a drawbar 15,a toolbar 14, and one or more row units 11 pulled by a motorizedself-propelled wheeled tractor 5. For ease of access, the samplepreparation sub-system 3002 and the chemical analysis sub-system 3003can be placed at either end of toolbar 14 or on drawbar 15 (eachpossible position illustrated in the figure). This allows a user toaccess the sample preparation sub-system 3002 and the chemical analysissub-system 3003 for maintenance or to replenish any materials.

FIG. 253 illustrates a combine harvester 20 having a collection area 21,a grain tank 23, a cross auger 22, a fountain auger 25, and a cleangrain elevator housing 24. Sample system 3001 can be disposed to pullsamples from collection area 21 or grain tank 23 and send grain to thesample preparation sub-system 3002 and the chemical analysis sub-system3003, which can be disposed on combine harvester 20 such as on one ormore available walls 26.

FIG. 254 illustrates a center pivot irrigation system 30 having acentral pivot 31 one or more movable wheeled supports 16 (16-A, 16-B,16-C, 16-D) with wheels 32 which rotate about central pivot 31, a commonlongitudinally-extending transport line conduit 34, one or moreconnection line conduits 35 (35-A, 35-B, 35-C, 35-D) fluidly coupled tothe transport line conduit 34, one or more valves 36 (36-A, 36-B, 36-C,36-D) (e.g. three-way valves shown or two-way valves) to selectivelyplace transport line conduit 34 into selectable fluid communication withone of connection line conduits 35 (35-A, 35-B, 35-C, 35-D), one or moresoil collection systems 3001 (3001-A, 3001-B, 3001-C, 3001-D) incommunication with connection line conduits 35 (35-A, 35-B, 35-C, 35-D),a vacuum source 37 fluidly connecting transport line conduit 34 to asample preparation sub-system 3002 and the chemical analysis sub-system3003. Optionally, a pressure source 38 (e.g. air pump) can be disposedat an end opposite the central pivot 31 to provide a motive pressureforce to move or convey samples through transport line 34 to the samplepreparation sub-system 3002 and the chemical analysis sub-system 3003.Pressure source 38 may be used in conjunction with or instead of vacuumsource 38. Valves 36-A, 36-B, 36-C, 36-D are in signal communicationwith CPU 2820 to provide selective opening from one soil collectionsystem 3001-A, 3001-B, 3001-C, 3001-D for processing and testing of soilat a given time. As illustrated, there are four sections in thisnon-limiting embodiment, but center pivot irrigation system 30 can havefewer or more sections depending on the length of the transport lineconduit 34 desired.

FIG. 255 illustrates a bailing system 40 having an accumulation frame41, a conveyor 42, a pickup 43, housing 45, and baler 44. A samplesystem 3001 can be disposed to pull a sample from conveyor 42 andtransport the sample via flow conduit 46 to the sample preparationsub-system 3002 and the chemical analysis sub-system 3003, which can bedisposed on housing 45 or any other convenient mounting location on thebailer that does not interfere with the operation of bailing system 40.

Mass Determination of Collected Soil Samples

In order to analyze the collected soil sample and determine the desiredchemical levels and characteristics such as nutrient content (i.e. ppm),and prepare the slurry with the desired water to soil ratio forprocessing, the amount (mass) of the raw soil sample processed throughthe systems and processes disclosed herein must be properly quantifiedand understood. Ideally, soil that does not have any moisture (e.g.sample which has been fully dried down) would be added to a known amountof water to create a slurry ratio used for downstreamprocedures/calculations. For example, adding 20 grams of dry soil to 40mL of water would generate a 2:1 water to soil ratio. The amount ofwater added to generate this ratio is dependent on both the amount ofsoil collected as well as its initial moisture content (whichpre-dilutes the slurry). Field collected soil samples however will verylikely not be completely dry. In order to understand the collected soilmakeup, mass and volume of the soil must measured to correctly andaccurately calculate and prepare the finalized slurry water to soilratio.

Some methods for “volumizing” and/or “massing” collected soil (or otheragricultural related samples that might be processed in the presentsystems such as stalk mass, manure, etc.) will now be described. Oneassembly and method for volumizing the soil sample using samplecollection/volumizing station 160-1 shown in FIGS. 14-18 has alreadybeen described elsewhere herein. Following are some additional examplesand approaches for volumizing and/or massing the soil sample whichincludes both various indirect and direct methodologies.

Indirect Volume/Mass:

A pneumatic/hydraulic piston or electric linear actuator may be used topress the collected soil into a cylindrical “plug.” This soil plug canbe made using a consistent force from sample to sample, such that thedensity is better understood. By using feedback such as pressure and/orspeed and/or electrical current and/or position of the piston oractuator, one can draw conclusions about the makeup of the soil. Forexample, if the soil compresses very little and then the measuredpressure/force climbs rapidly, it can be concluded that the soil likelydoes not have a lot of moisture present. If the soil continues tocompress as force slowly climbs, we may also make a conclusion about itstexture (i.e.: sand, high organic matter) based on the response—in thiscase that the soil has a high organic matter content and is not dry.FIG. 281 is a graph depicting actual measured piston displacement vs.compressive force (psi) from testing performed on various soil typesutilizing the compression apparatus shown in FIG. 282 as furtherdescribed below. Each line in the graph represents a different soilsample, which were of different types and composition such as organicmatter (OM), moisture content, particle size, etc. The graphdemonstrates the effect that soil type and composition have on pistondisplacement and force required to compress the soil sample using thedevice of FIG. 282.

FIG. 282 depicts a compression apparatus 5900 which includes acompressing member 5902 coupled to an actuator be a hydraulic orpneumatic piston type or electric linear actuator 5907. The apparatus isconfigured and operable to compress a soil sample plug in conjunctionwith determining its “as collected” moisture content. By compressing thesoil into a plug, it is possible to calculate the soil's volume based onpiston or actuator position. This result can be used to calculate otherrequired measurements (i.e. how much soil was collected, how much waterwill need to be added to make a slurry, etc.).

The apparatus 5900 includes an elongated hollow cylinder 5904 definingan internal cylinder bore or chamber 5905 which receives and holds thecollected soil plug. Cylinder 5904 may be cylindrical with an annularcircular cross-sectional shape that defines the chamber in oneembodiment as illustrated. In one representative non-limiting example, a¾ inch bore was used for processing soil samples. The apparatus includesan inlet 5903 for adding the soil sample to the chamber and an outlet5906. The inlet may be adjacent to the top of the cylinder and theoutlet may be at the bottom. The outlet may be controlled by anopenable/closeable gate 5901 such as provided by a gate valve 5911(represented schematically) which selectively closes or opens the outlet5906. The gate 5901 is preferably flat and defines a top surface againstwhich the soil is compressed by compressing member 5902 for compaction.The inlet 5903 may be a tube or piping segment which may be controlledby a gate valve 5911 or other type valve for adding soil to the cylinderat selected times. The compressing member 5902 is slideably movablevertically within chamber 5905 from an upper position to a lowerposition for compressing the soil sample. Other orientations of theapparatus and cylinder may be used in other embodiments includinghorizontal and a plurality of angular positions therebetween.Compressing member 5902 may have a cylindrical solid body and be coupledto actuator 5907 by an operating rod 5910 which may be cylindrical inone embodiment. FIG. 282 shows an example of actuator 5907 in the formof a hydraulic or pneumatic cylinder including an inlet 5908 forintroducing a working fluid to activate the compressing member 5902 andan outlet 5909 for discharging the working fluid. The working fluid maybe oil or air. The actuator may also be an electric linear actuator insome embodiments.

In operation of apparatus 5900, a soil sample plug is first added tochamber 5905 via inlet 5903 with compressing member 5902 being in anupper position. Actuator 5907 is then actuated either hydraulically,pneumatically, or electrically depending on the type provided. The soilsample is compressed as the compressing member moves downward towardsthe outlet of the cylinder 5904 into a lower position. As thecompressing member moves to the lower position while compressing thesoil sample, the compression force applied by the actuator is measuredusing a sensor 5912 which may be a force-type sensor or aposition/displacement type sensor either of which are commerciallyavailable and known in the art. Sensor 5912 may be operably andcommunicably coupled via a wired or wireless communication link 5752 totransmit the measured force or displacement to the system controller2820 which may control operation of the apparatus 5900. The measuredforce or displacement is then used by the controller to calculate themoisture content of the soil sample in its “as collected” condition tothen determine the amount of water required to be added to the soil toachieve the desired predetermined soil to moisture ratio for creation ofthe soil slurry to be further analyzed by the systems disclosed herein.

Direct Volume:

Once the soil is in a closed container, the volume of the soil can becalculated using a derivation of the Ideal Gas Law. Using assumptions,the equation can thus be reduced to: V1*P1/T1=V2*P2/T2 where V1 is thevolume of an independent reference container 5923 of fixed known volume,and V2 is the mixing chamber volume of the mixing container with bladeassembly 141 minus the input soil and/or water plus the V1 chamber andany valves and passages. The mixing chamber may be provided by mixingcontainer 101 of mixer-filter apparatus 100 in some embodiments, whichhas internal mixing chamber 102 that defines V2 (see, e.g. FIGS. 3-12)or variations thereof.

FIG. 284 is schematic diagram of one non-limiting embodiment of avolumetric and mass based analysis system 5999 for determining the massand moisture content of a collected “raw” soil plug or sample utilizingmixing container 101 of the mixer-filter apparatus 100 previouslydescribed herein. The system shown includes equipment and provisions forvolumizing the soil sample, adding water to form the slurry for furtherprocessing and analysis in the systems disclosed herein, and weighingthe slurry using a weighing device. These foregoing basic steps are usedand followed for preparing the water and soil slurry mixture in allinstances described herein. Although the weighing device shown forconvenience is a weigh coil 5960 described further below, it will beappreciated that the other weighing devices enumerated below mayalternatively be used and substituted for the coil shown in the systemof FIG. 284. Reference is also made to FIGS. 286 and 287 which shows analternative arrangement of the mixing container 101 further describedbelow and labeled with reference numeral 101A.

Referring now to FIGS. 284 and 286-287, the process for “volumizing” thesoil sample using the “direct volume” method may be performed as followsin some embodiments. The process and system components/equipment whichfollow may be automatically controlled by programmable system controller2820. Accordingly, the components/equipment are all operably andcommunicably linked to the controller 2820 via wired and/or wirelesscommunication links 5752 described and shown elsewhere. Representativelinks 5752 are only shown in FIG. 284 to prevent obscuring the image.The fluid components and containers shown are fluidly coupled togetherin the manner shown by a suitable enclosed flow conduit 6006, which maybe piping or tubing. Flow conduit 6006 in this portion of the system isan air conduit. Different flow conduits 6006 in system 5999 are used fordifferent purposes defined by their location and uses in the system asshown in FIG. 284 and described herein. Accordingly, such flow conduits6006 are designated with the common reference number 6006 forconvenience whose purpose varies with the particular type of fluidhandled.

Before the cycle begins, isolation valve 5921 between containers 101 and5923 opens (via controller 2820) and a atmospheric/zero pressure readingmay be optionally taken of volume V1 in container 5923 such as via apressure sensor 5925. To record the pressure, the bottom drain valve5927 associated with mixing container 101, which may be formed byvertically movable and sealable stopper 131 previously described hereinin detail, is first placed in an open position thereby allowing themixing chamber 102 (volume V2 of container 101) to reach ambientatmospheric pressure. With isolation valve 5921 open, the pressuresbetween volumes V2 and V1 equalize thereby bringing the pressuremeasured inside volume V1 of container 5923 to the same atmosphericpressure which is measured by sensor 5925. After the pressure reading istaken by the sensor and received by programmable controller 2820 whichcloses the mixing container drain valve 5927 thereby sealing mixingchamber 102 inside mixing container 101. Isolation valve 5921 is alsoclosed by controller 2820.

Next, the soil sample is then added to the closed mixing container 101of known empty volume V2 (i.e. of mixing chamber 102) via a soil loadingvalve 5926 fluidly coupled to the soil inlet of the container, which maybe a pinch valve 160 in some non-limiting embodiment as previouslydescribed herein. Other type valves of course may be used. An optionalvolumization step (similar to the Ideal Gas Law calibration anddescribed further below) may occur here to determine the “bulk” densityof the soil (soil with entrapped air). Either based on this volumizationstep or using sample collection assumptions, a known volume of water isthen added to the soil via water pump 6100 through the water inlet ofthe container 101, which may be a positive displacement pump in someembodiments (e.g. micropump 5760 in FIGS. 256-258 or water pump 3304 inFIG. 261 previously described herein). Other type water pumps may ofcourse be used, which could include a timed pressure over orifice pump.In some variations of the present process, the water may instead beadded to mixing container 101 before the soil.

The soil loading valve 5926 is next closed after the water and soil arein mixing container 101. The soil/water mixture is blended via motordriven blade assembly 141 in the manner previously described herein tohomogenize the sample and remove entrapped air. A vacuum may optionallybe applied via a vacuum pump 5928 connected to mixing chamber 102 (shownin dashed lines) to further remove air and also reduce error in theP1/P2 measurement. With isolation valve 5921 still in the closedposition, air inlet valve 5929 opens to “charge” the reference container5923 (defining volume V1). After a few seconds, inlet valve 5929 isclosed by programmable controller 2820 and the pressurized air istrapped in container 5923 (V1). The pressure sensor 5925 takes a readingP1 and temperature sensor 5930 records temperature T1 in container 5923which are each recorded by the sensors and transmitted to controller2820.

If not already done, controller 2820 closes all valves fluidlyconnecting to mixing container 101 (e.g. isolation valve 5921, soilloading valve 5926, drain valve 5927, etc.) which forms a pressure sealof mixing chamber 102 therein. Next, isolation valve 5921 opens andafter equalization of pressures between containers 101 and 5923, a newpressure reading P2 is recorded by pressure sensor 5925 and temperaturereading T2 is taken by temperature sensor 5920 operably coupled tomixing container 101. The temperature could alternately be read bytemperature sensor 5930 in reference container 5923, such that only onetemperature sensor is needed. It bears noting that any suitablecommercially available mechanical and/or electronic temperature andpressure sensors may be used for this process, which are well known inthe art without undue elaboration.

Using the actual readings recorded by the sensors, the slurry volume isnext solved using equation: Vsoil+Vwater=V1+V2−(P1/P2)*(T2/T1)*V1 whichmay be executed and calculated by programmable controller 2820 via asuitable preprogrammed algorithm. It should be appreciated that therelationship of soil sample volume to sensor readings will likely notfollow the Ideal Gas Law completely, and thus an alternative calculationthat can be determined empirically through regression can model thesystem behavior. In this case, values such as P1/P2, P2 ², P1*P2, T2, etcetera may be used to determine the sample volume by applying factorsand offsets.

For improved accuracy, the system can be made “robust” against changesin container volume and other disturbances that occur over time by meansof a volume calibration. On an as-needed basis, a calibration proceduremay be used which will add a known amount of water to the mixing chamber102 of mixing container 101. The above steps can be followed todetermine volume. This could be repeated with multiple volume levels toestablish a relationship between pressure ratios and volume and used inthe volume determination of soil slurry. Alternatively, the calibrationcould be done with an empty mixing chamber 102 or even by opening thechamber to another reference chamber similar to V1.

After the volumizing step is completed, a small reference portion (i.e.“representative sample”) of the filtered slurry is extracted from mixingchamber 102 of mixer-filter apparatus 100 and directed to flowdownstream to the weighing device (e.g. weigh coil 5960 as shown orother weighing device described herein) via slurry sample drain flowconduit 6006 controlled by openable/closeable reference slurry valve6011. This small extracted portion or sample of slurry is representativeof the water to soil ratio for the majority of slurry remaining in themixing chamber 102 which will be used to determine the chemicalcharacteristic/properties of the slurry (e.g. nitrogen, calcium,phosphorus, etc.). The weigh coil and other weighing devices allowdetermination of the weight of the slurry needed to determine thepresent water to soil ratio so that the amount of water needed to beadded to the mixing chamber 102 (if any) to achieve the desired targetwater to soil ratio preprogrammed into controller 2820 may be achieved.The slurry weight determination methods and weigh devices are furtherdescribed below under the discussion related to Direct Mass approaches.

FIG. 285 shows an alternative apparatus for the purpose of volumization.Volume can be measured by means of a level sensor 5941 in referencecontainer 5940 of known dimensions and volume. A known amount of wateris added to the soil which is placed in container 5940. The soil/watermixture is blended to homogenize the sample and remove entrapped air. Avacuum may then be applied to further remove air (e.g. vacuum pump5928). The level of slurry mixture inside container 5940 is thenmeasured using either (a) a continuous level sensor 5943 (e.g.ultrasonic, laser or capacitance), or by continually adding water to thecontainer until a level switch 5944 is tripped in a sensing standpipe5941 fluidly coupled to the bottom of the chamber in the container toindicate a known volume.

Referring to FIGS. 286 and 287, the alternative mixing container 101Anoted above differs primarily from the previous apparatus 101 shown inFIGS. 3-21 in the re-arrangement of the motor 126 to instead be mountedabove. This avoids wetting the motor each time the slurry contents ofthe container are dumped out of the bottom of the mixing container 101Aby opening the stopper 131 which serves as the container drain valve.The alternate mixing container 101A is similar in other respects whichwill not be repeated again here for sake of brevity. The soil loadingvalve 5926 and reference container 5923 previously described herein arealso shown. FIG. 286 shows mixing container 101A in a closedposition—stopper 131 engaged with and sealing the bottom containercleanout port 105. FIG. 287 shows the open position—stopper 131displaced downwards and dis-engaging cleanout port 105 to dump thecontents of the mixing chamber 102. The stopper assembly may be movedvertically and linearly between upper sealed and lower unsealedpositions via a suitable pneumatic, hydraulic, or electric actuator 5945(shown schematically) coupled to operating shaft 5946, or a plurality ofactuators.

Direct Mass:

A first approach using a direct mass method for “massing” the soilsample utilizes the soil sample in a “field collected” condition whichmay be referred to a “dry” mass method (albeit the sample may have someinitial moisture content in the condition extracted from theagricultural field). The term “dry” is used to connote that noadditional water is added to the sample for processing at this point inprocess in order to determine its mass, in contrast to a “wet” directmass method described below. Referring to FIG. 283, the soil sample canbe transferred to a weigh container 5950 from the soil collectionapparatus (which may be any of those disclosed herein or others). Thecontainer may be any suitable type of metallic or non-metallic container(e.g. polymeric) and shape. A cylindrical container may be used in oneembodiment. The container 5950 is equipped with an openable/closeablegate 5951 at its base or bottom. Any suitable type of manual orautomatically actuated (e.g. pneumatic, hydraulic, or electric) gateactuation mechanism 5953 may be used. The gate is initially closed whilesoil is loaded into the volumetric container such as via a soil loadingpinch valve 160 of the type previously described herein, or anotherapparatus. After the soil is loaded, its mass can be determined byseveral methods. For example, a strain gauge 5952 may be attached to arigid sidewall or bottom of the container 5950 at one end and to a rigidsupport structure S at an opposite end, thereby supporting the containerin a cantilevered manner as shown. An initial strain gauge reading maybe obtained with an empty or water filled container 5950. After loadingthe soil into the container, the added weight will cause the straingauge to deform which can provide a second loaded reading which can bemeasured via the programmable controller 2820 operably coupled to thestrain gauge. The differential in strain gauge readings can be used bythe controller to quantify the mass and weight of the soil. For bettersensitivity, the container 5950 could be lighter weight if the gateactuation mechanism 5953 were not rigidly attached to and supported bythe weigh container, but instead supported separately via a suitablesupport structure. An example of this arrangement is shown in FIG. 288.

A “wet” direct mass method for “massing” the soil sample includes firstadding water (moisture) to the collected sample and thoroughly mixingthe mixture to produce slurry which can then be weighed. The method orprocess may include the following steps. Optionally estimate volumeinitially using the Ideal Gas Law method above with system shown in FIG.284. Add a predetermined amount of water that ensures that the ratio isless than the final desired ratio (for example, add water to make awater to soil ratio of about 1.6 if targeting a ratio of 2.0). Mix thewater and soil to prepare a slurry by blending using mixing container101 or 101A. Pump (e.g. peristaltic or pressure) the slurry into aweighing device of known volume to obtain the weight of the slurry. Theweighing device used may be any of the following examples of typedevices described in further detail below.

A first example of a weighing device for weighing the slurry is a coiledweigh tube or “weigh coil” 5960 shown in system diagram of FIG. 284, andin isolation in FIG. 289. The weigh coil is preferably constructed withas few interruptions as possible and of similar diameter throughout, soas to avoid getting air pockets, and to improve clog-free flow and alsocleanout. The weigh coil should also preferably be as thin walled aspossible to keep weight to a minimum. A feature of the weight coil ishaving a fixed volume in order to calculate the density of the slurry.The coil 5960 may be valved at both inlet and outlet ends by inlet andexit/outlet valves 5961, 5962, as shown, or alternatively open toatmosphere in other embodiments (not shown). The weigh coil 5960 may besupported by a support structure, such as a tubing manifold block 5963or simply a support structure without tube connection provisions. Straingauge 5952 is coupled between the manifold block and coils of weigh coil5960 for measuring the change in strain created by the downwarddeflection of the coils when loaded with slurry versus empty or waterfilled to determine the weight of the slurry. Any suitable commerciallyavailable strain gauge may be used for this or any of the strain gaugesdescribed herein.

FIG. 301 is a schematic diagram showing a slurry weigh station 6000configured for weighing a small sample portion of the already mixed andprepared soil slurry with provisions for additionally volumizing theslurry mixture sample. This weigh station is located downstream of thevolumizing and mixing system shown in FIG. 284, and thus receives theslurry sample from the mixer-filter apparatus 100. Station 6000 includesan example of a weighing device in the form of a slurry weigh container6005 having an associated weigh scale 6004 for obtaining a direct weightof the slurry in the container. The design and arrangement of the weighstation 6000 with volumizing provisions is similar to that shown in FIG.284 including many of the same fluid components. However, themixer-filter apparatus 100 is replaced by simply the slurry weighcontainer 6005 of known volume V2 which is used in conjunction withreference container 5923. Since slurry weigh container 6005 contains nomoving parts, blades, piston actuators, filters, etc. like themixer-filter apparatus 100, it is easier to accurately measure theweight of the slurry by weighing the container once filled and comparingthat to the tare weight of the container.

The weigh system 6000 further includes a slurry inlet valve 6001 fluidlycoupled to the container inlet port 6007 at top via flow conduit 6006and which receives the prepared slurry from mixer-filter apparatus 100,and waste valve 6002 fluidly coupled to the container outlet port 6008at bottom. The reference container 5929 and other valving shown is thesame as described for FIG. 284. In operation, a small representativesample of the mixed slurry is transferred from mixer-filter apparatus100 shown in FIG. 284 through slurry valve 6011 and flows into internalchamber 6009 of a slurry weigh container 6005 after. The slurry samplevolume is determined using the same Ideal Gas Law equations andmethodology already described above with respect to FIG. 284.Accordingly, the entire “volumizing” step will not be described here forbrevity. After the volumizing process of the slurry sample is completed,all valving to the container 6005 is closed and the slurry weight ismeasured by a scale 6004 coupled to the container (shown schematicallyin figure). The difference between the empty container (tare weight) andfilled container 6005 allows determination of the actual slurry weight.Any suitable commercially-available scale may be used.

In yet another example of a weighing device, slurry fluid fills a knownvolume provided by a tubular container 5964 from the bottom and pushesair out the top as it fills. Container 5964 may have an elongatedtubular body of relatively uniform diameter and includes a top outletport 5966, bottom inlet port 5967, and an internal chamber 5965extending between the ports along an axis. A three-way inlet valve 5968may be fluidly coupled to inlet port 5967 via an enclosed flow conduit5970 which may be tubing or piping. A three-way outlet valve 5969 isfluidly coupled to outlet port 5966 via a similar flow conduit. Theremaining ports of the valves may be coupled to flow conduits as shown.FIG. 290 shows the valving position for filling container 5964 withslurry. FIG. 291 shows the valving positions for cleaning by introducingwater in a reverse direction downwards through the container from above.The container 5964 is supported by a strain gauge (not shown) thatmeasures the strain induced by deflection of the container under theweight of the slurry.

In yet another example, a “teapot” shaped container 5971 of known volumeshown in FIG. 292 may be used as the weighing device and filled withslurry to the point of overflowing. The container includes upper slurryinlet port 5972, lower waste outlet port 5973 normally closed by wastevalve 5976, and vent/overfill port 5974 at the uppermost portion or topof the container which fluidly communicates with atmosphere or anexhaust line connected to atmosphere. Each port is fluidly connected tointernal chamber 5975 for receiving and weighing the slurry. Chamber5975 may have a polygonal cross-sectional shape in some embodiments;however, other shaped chambers may be used. The slurry inlet port iscontrolled by isolation valve 5977. For cleaning, valve 5976 at the baseopens for draining. The container 5971 is supported in a cantileveredmanner by strain gauge 5952 which measures the strain induced bydeflection of the container under the weight of the slurry.

In yet another example of a weighing device, the microfluidic pumpingchamber 5765 shown in FIGS. 257-258 may be used.

After any of the foregoing weighing devices, the weight may nextdetermined such as via the strain gauge 5952 associated with eachdevice. It bears noting that the slurry weight preferably should be alarge part of the overall mass of any of the foregoing weighing devicesto reduce noise when measuring dynamically. The weight measurement couldbe done on a continuous slurry flow basis (for better averaging) or bystopping the pump and taking a static weight measurement. The slurryinlet for the weigh chamber may be through a separate filter than thedownstream filtered slurry for more volume or to allow larger particlesinto the weigh chamber of the devices. Accordingly, the inlet filter tothe weighing device containers may have larger sized openings than thedownstream filters.

Accordingly, the slurry weight measurement may be done by attaching theweighed portion of the weighing devices or containers (i.e. load cell)to a support structure by using a strain gauge according to any of theapproaches described above.

Accordingly, the slurry could be recirculated back into the mixingchamber instead of being wasted in order to preserve the most sampleaccording to any of the approaches described above.

Alternatively, other embodiments, the slurry weight measurement may bedone by measuring sinusoidal response to sinusoidal or random systemdynamic input. The slurry mass can thus be estimated by using therelationship between output frequency or natural frequency and mass inwhich the weight measurement is obtained by measuring frequency responseof the weigh coil 5960 to a predetermined or random external excitation.For example, in the embodiment shown FIG. 293, the slurry may be loadedinto the weigh coil 5960 and the coil is then excited by means ofelectro-mechanical plunger which strikes the coil with a constant fixedforce. This frequency response weigh device assembly includes weigh coil5960 supported in cantilevered manner from support structure 5963, alinearly movable excitation plunger 5978 which acts on a target surfacedefined by a vibration measurement protrusion 5980 integrally formedwith or rigidly attached to the coil, and an electronic vibration sensor5979. Sensor 5979 is positioned either proximate to but no contactingthe vibration measurement protrusion 5980 for a non-contact typevibration sensor, or in contact with protrusion 5980 for contact-typevibration sensor. The sensor is configured and operable to measure thefrequency response of the coil due to excitation by the plunger. Thevibration measurement protrusion 5980 is located within the strikingrange of the plunger 5978. Any suitable type of contact or non-contactvibration sensor 5979 may be used, such as for example withoutlimitation contact-type strain gauge based transducers, piezoelectric(“piezo”) sensors, accelerometers, non-contact type capacitive oreddy-current displacement sensors, or others. The sensor 5979 isoperable to transmit the measured vibration frequency of the weigh coil5960 to system controller 2820.

The equation which describes natural frequency is:

${fn} = {\frac{1}{2\pi}\sqrt{K}\text{/}M\mspace{14mu}{\left( {{cycles}\text{/}{second}} \right).}}$

In operation, the plunger 5978 strikes the vibration measurementprotrusion 5980 which induces vibration of the coil; the frequency ofthe vibrating coil being detected and measured by the sensor 5979.Because the natural frequency of the vibrating coil will change betweenan empty state and a weighted state filled with the slurry, the changein frequency response attributable to the weight of the slurry betweenthese states can be measured by the frequency sensor and used by systemcontroller 2820 to calculate the weight of the slurry. This change infrequency is thus correlated to the slurry mass/weight. When themassing/volumizing system is mounted on vehicle in motion traversing theagricultural field during soil sample collection, the material stiffnessof the weigh coil 5960 will be chosen such that frequency of oscillationwill be above disturbance frequency encountered by a vehicle moving overterrain thereby avoiding interference. It bears noting that the slurrymay be weighed in either batch mode (i.e. fill and empty the coilbetween weight measurements) or by a continuous flow through the coileither of which is compared to a preprogrammed baseline “empty”frequency value stored in controller 2820.

In an alternative vibration frequency based weighing device shown inFIG. 294, an emitting piezo transducer 5982 excited at a specifiedpredetermined frequency is mounted on one end of the weigh coil 5960 toexcite the coil (i.e. induce vibration), and a separate receiving piezotransducer 5981 which may be used as a receiver may be mounted on theopposite end of the weigh coil. Each transducer is operably andcommunicable linked to the programmable system controller 2820 and theiroperation is controlled by the controller. The amplitude, frequency, orphase shift will be measured and then correlated to soil mass or weightby the programmable system controller 2820.

To isolate the tubing connections from affecting the weighing device orload cell and weight measurement accuracy, the strain in the weigh coil5960 may be applied to a custom load cell 5983 that has the tube passage5984 running through it with inlet and outlet fittings 5985, 5986 oneach end for tubing connections as shown in FIGS. 297 and 298. Load cell5983 may have a solid rectangular cuboid body in one embodiment;however, other shapes may be used.

In some embodiments, the fluid tubing connections themselves may be usedas the strain gauge as shown in FIG. 295. Each straight end of the weighcoil is rigidly mounted to a support structure 5954 in a cantileveredmanner as shown. A magnet 5988 is mounted to the coiled portion of theweigh coil at a side opposite the tubing ends which are on the same sideof the coil. Loading the weigh coil with slurry causes the cantileveredcoil to deflect downwards under the weight of the added slurry. This inturn changes the position of the magnet 5988 relative to a locatedproximity sensor 5989 such as a Hall effect sensor, which measures thechange in magnitude of a magnetic field. The output voltage is directlyproportional to the magnetic field strength and is transmitted to thesystem controller 2820. The controller compares an “empty coil” baselinevoltage corresponding to the magnet field with the measured “full coil”voltage to correlate a weight of the slurry.

In yet other embodiments, the weigh coil 5960 tubing connections may beisolated for measuring the weight of slurry in the coil by docking andundocking the tube inlet and outlet end connections. This is shown inFIG. 296. Quick-connect type tubing connectors 5990 may be used whichare commercially available. The weigh coil 5960 is supported in acantilevered manner by the strain gauge 5952 having one end rigidlycoupled to the coil and the opposite end rigidly mounted to a supportstructure 5954. Either the weigh coil or the tubing connections may bemovable to dock and undock the weigh coil. Preferably, the dockingconnection is at least the highest point in the system to avoid anyfluid loss (not shown). The weigh coil is first docked to fill the coilwith slurry. The weigh coil is then undocked and the strain gaugemeasures the strain of the cantilevered coil which is transmitted to theprogrammable system controller 2820 for determining the weight of theslurry by comparing the measured strain to a preprogrammed baselinestrain.

It bears noting that isolation mounting of the weighing device or loadcell is important when determining mass to reduce some of the dynamicinterference. Two possible methods for isolation are shown in FIGS. 299and 300 for mounting certain configurations of weighing device otherthan a coil such as a container or other device with a frame or supportmember. In FIG. 299, isolation of the supported member 5991 of theweighing device is through a compliant material (such as rubber, NBR,SBR, etc.) of the vibration dampener 5992. In FIG. 300, isolation isachieved by the unique compliant structure and shape of the dampener5992 which may include a central opening or multiple openings.

Returning now to the process of volumizing and massing the soil sample,once the small extracted slurry sample is weighed via any of theforegoing weighing devices, the water and slurry mixture can now beunderstood and characterized using the following equation to determinethe percentage of water and soil content of the slurry: Volumesoil=(Weight total−Volume Total*density water)/(density soil−densitywater). Assuming water density=1 and soil density=2.55 g/mL, if totalvolume is 10 mL and the total slurry weight is 13 g, then Volumesoil=1.935 mL and therefore water volume is 8.065 mL and soil mass is4.934 g. That gives a slurry ratio of 8.065/4.934=1.634. This valuetells us the makeup of the homogenous slurry ratio remaining in themixer-filter apparatus 100 since the small extracted portion of slurrywhich was weighed is representative of the slurry in the mixer-filterapparatus. To get the precise ratio output needed (i.e.: 2:1), theslurry volume left in the mixer can be re-volumized (using Ideal GasLaw). The appropriate amount of additional water needed to achieve thetarget desired water to soil ratio is then added to the slurry andremixed.

For making an accurate water to soil slurry ratio, it is important to beable to add the correct amount of water to the mixing chamber 102 ofmixing container 101 or other device to which water will be added to thesoil or slurry. One possible method for this is using multiple pumpingchambers of varying volume. In one embodiment, to be able to get thecorrect amount of water, a selection of different size water pumpshaving different volumetric capacity pumping chambers can be utilized.For example, a 10 mL, 5 mL, 1 mL and 0.1 mL pump could be used in thefollowing way: To add 44.2 mL of water, use 4×10 mL, 4×1 mL, 2×0.1 mL;or To add 37.6 mL of water, use 3×10 mL, 1×5 mL, 2×1 mL, 6×0.1 mL. Anysuitable type water pumps may be used. In one embodiment, multipledifferent size stand-alone water diaphragm pumps 5760 having aconfiguration similar to that shown in FIGS. 256-258 may be provided formetering the proper amount of water for the slurry. Diaphragm pump canbe a separate pump from diaphragm valves described below, or thediaphragm pump can be both a diaphragm pump and a diaphragm valve. Whenused throughout, a recitation to a diaphragm pump and a diaphragm valverefers to each individually or to a diaphragm pump that performs as botha pump and a valve.

In order to transport soil and/or slurry, it is important to not allowbuildup or friction on various components. To reduce the possibility ofthis, portions of components which come into contact with the soil orslurry could be coated with a hydrophobic, super hydrophobic, omniphobicor fluoropolymer coating. Other components could be made from UHMW orHDPE or other low surface energy base material, such as fluoropolymers.Tubing could be made of a fluoropolymer, such as FEP (FluorinatedEthylene Propylene) or other materials.

End users may want the option to use the device without the soilcollection mechanism which automatically transfers the collected soil tothe slurry mixing chamber 102 of the mixer such as mixing container 101.This would allow the device to be used on a lab bench or would allow theuser to input soil using a different collection techniques (such asdeeper cores). The mixing chamber could thus be outfitted with a funnelor container to allow the user to manually load the chamber in analternate fashion.

Following is a high level summary of a method for preparing a soilslurry with desired target water to soil ratio for chemical analysis ofthe soil sample using the foregoing volumizing and massing techniquesand apparatuses. The process to be described uses illustrative butnon-limiting numerical values {in brackets} to more clearly demonstratethe process and parameters involved by example. It will be recognized,however, that the illustrative values do not limit the method orinvention. The steps below may be all performed automatically by systemcontroller 2820, manually, or a combination thereof.

The following assumptions may be made: There is a somewhat consistentvolume of soil coming in, which has a somewhat consistent density acrossall samples; “Particle” density of soil is constant (same across allsoils); Effects of atmospheric temperature, pressure, etc. are limitedor are empirically calibrated out; Temperature effects frompressurizing/depressuring are negligible; Final slurry target outputratio is 3:1 (water mass to soil mass); and Water density is constant (1g/mL).

With these assumptions, the method or process includes the followingbasic steps with initial reference to FIG. 284 showing the volumetricand mass based analysis system 5999 previously described herein fordetermining the moisture content of a collected “raw” soil plug orsample utilizing mixing container 101 of the mixer-filter apparatus 100.

Mixing chamber 102 (V2) of mixer-filter apparatus 100 is prepared toreceive the raw soil by closing the drain valve 131 and closing the mainand reference slurry outlet valves 6010, 6011 (filtered slurry todownstream and filtered slurry to weigh coil). The water pump 6100accurately dispenses a preprogrammed predetermined volume of water {100mL} into the mixer and the motor is turned on slow speed {1,000 rpm}.

A preprogrammed predetermined amount of soil is then blown from thecollection device via a pulse of pressurized air from the air compressorassociated with the soil collection system or air compressor 3030 (see,e.g. FIG. 1) into mixing chamber 102 via soil loading valve 5926 (e.g.pinch valve 160) {˜38.5 mL of 5% gravimetric water content soil—47 gsoil and 2.474 g water}. The soil loading (pinch) valve 5926 is thenclosed. Alternatively, the soil may be added first to mixing chamber 102and followed by adding the predetermined volume of water.

The water/soil mixture is blended into a homogeneous slurry by pulsingthe mixer at high speed {15,000 rpm}, then slowed to stirring {600 rpm}.Slurry ratio is set {(100+2.474)/47=2.18}.

The filtered slurry to weigh coil 5960 reference slurry drain valve 6011is opened and begins to waste out. The soil is then “pumped” bypressuring the V2 volume mixing chamber 102 {15 psi} via air compressor3030 or another air source into weigh coil 5960. During this time,continuous weight (e.g. via strain gauge or other coil weighingtechniques described above) readings {13 g} are taken on the weigh loop.Slurry ratio is calculated, either manually or via system controller2820.

Volume soil=(Weight total−Volume Total*density water)/(densitysoil−density water) Assuming water density=1 and soil density=2.55 g/mL,then Volume soil={1.524 mL} and therefore water volume is {8.476 mL} andsoil mass is {3.887 g}. That yields a slurry ratio of8.476/3.887={2.18}.

The filtered slurry to weigh coil reference slurry valve 6011 closes andair pumping pressure is removed.

Since the current slurry's water-to-soil ratio is now known, the properadjustment can be made to move to an example target ratio of 3:1 waterto soil once we know the volume of slurry remaining. The controller 2820may compare the now known initial water to soil ratio to a target waterto soil ratio preprogrammed into the controller. Alternatively, thiscomparison can be performed manually. Next, air supply pressure airinlet valve 5929 opens to “charge” the V1 volume chamber defined byreference container 5923 with air. After a few seconds, valve 5929closes and the pressurized air is trapped in volume V1 of the referencecontainer. The pressure sensor 5925 takes a reading (P1).

All valves fluidly connected to volume V2 of the mixer-filter apparatusmixing chamber 102 are closed to create a sealed chamber or volume. Thisincludes stopper 131 (outlet valve 5927, and slurry valves 6010, 6011fluidly coupled to mixing chamber 102 through the stopper assembly.Next, isolation valve 5921 opens and after pressure equalization withthe reference container 5923 now in fluid communication through thevalve with mixing chamber 102, a pressure reading (P2) is taken.

The slurry volume is next solved: V slurry=V1+V2−(P1/P2)*V1*calibrationfactor. V1={150 mL} and V2={150 mL} in one embodiment. Vslurry=150+150−(45 psia/33 psia)*150*1.1={105 mL}. Slurry ratio=WaterMass/Soil Mass=Vol water*1/Vol soil*2.55={2.18}. Vol water+Vol soil={105mL} therefore Vol water={2.18*2.55*105/(2.18*2.55+1)=88.99 mL} and Volsoil={105-88.99=16.01 mL=40.826 g}.

To produce the desired target 3:1 water to soil ratio: {40.826g*3=122.48 g} of additional water is needed. Since we already have{88.99 mL} of that amount of water, need to add {33.49 mL} more water tothe existing slurry mixture. The water pump 5924 accurately dispensesthe additional water {33.49 mL} into the mixer 100 and the motor 126 isturned on {15,000 rpm} to re-homogenize the slurry mixture with theadded amount of water. The target 3:1 water to soil ratio is thusachieved.

With the fully prepared soil slurry now having the final water to soilratio of 3:1, the motor is idled and the filtered slurry is then pumpedto any of the downstream processes previously described herein forchemical analysis via first opening the main slurry outlet valve 6010with the main bottom drain valve 5927 (e.g. vertically movable stopper131) of mixing container 101 remaining in the sealed closed position toseal the mixing chamber 102 of mixer-filter apparatus 100. Air pressureis again applied to mixing chamber 102 by air compressor 3030 or anotherair source as before which drives the soil slurry to the next downstreamstation via slurry outlet valve 6010 for chemical processing andanalysis as indicated in FIG. 284. After removing the slurry for chamberanalysis, the main the bottom drain valve 5927 associated withmixer-filter apparatus 100 (e.g. stopper 131) is opened to purge anddump the excess slurry remnants in the mixing chamber 102. A cleaningcycle follows to prepare for the next sample by rinsing the mixingchamber 102 with filtered water.

Variations in the foregoing sequence/steps and components of the methodor process are possible.

Utilizing the system of FIG. 284, basic steps which may be automaticallycontrolled and operated by the programmable controller 2820 may be asfollows via suitable preprogrammed computer instructions or controllogic. The controller may be configured to: open the soil inlet loadingvalve 5926 to add the soil sample to the mixing chamber; operate thewater pump to add water to the mixing chamber 102; operate the mixerblade assembly to prepare the slurry; open the reference slurry outletvalve 6011, whereby a portion of the slurry flows into the weighingdevice 5960; and obtain a weight of the slurry from the weighing device.The controller may be further configured to add additional water to theslurry in the mixing chamber in accordance with a preprogrammed targetwater to soil ratio, operate the blade assembly again to remix theadditional water and slurry, open the main slurry outlet valve 6010 totransfer the remixed slurry to any of chemical analysis systems and/ordevices previously described herein to measure an analyte in the remixedslurry.

Process Water Filtration System

FIGS. 264-266 show a system and select components for filtering processwater for use in the soil sample analysis processing systems disclosedherein. The process water is used for creating the soil slurry and/orcleaning portions of the sample processing system between differentsample runs. These figures show one non-limiting embodiment in which thewater filtration system 5751 which may be mounted on the soil samplecollection/processing vehicle in one embodiment. In essence, the vehicleis a portable and mobile sample collection/processing lab on wheels. Inother embodiments, the water filtration system may be mounted on astationary support or apparatus. One possible embodiment of a wheeledand self-propelled sample collection/processing vehicle 5750 is shownwhich may include an electric or internal combustion engine coupled to aconventional drive train which drives the wheels to power the vehiclethrough the agricultural field. The vehicle has an on-board powersupply. Other types of vehicles, some of which are disclosed herein, mayof course be used. The type of self-propelled vehicles or agriculturalequipment, or pulled vehicles or equipment may be used and is notlimiting of the invention in any respect.

As shown, the water filtration system 5751 is mounted on vehicle 5750along with the sample processing “factory” 5747 which includes thesample preparation sub-system 3002 and chemical analysis sub-system 3003and its components, the sample probe collection apparatus 5748 whichincludes sample probe collection sub-system 3001, and processor-basedprogrammable controller, such as for example central processing unit(CPU) 2820. The programmable controller may be operably and communicablycoupled via communication wired and/or wireless communication links 5752to the water filtration system 5751 components and sub-systems 3001-3003components to control part of or the entire soil sample collection andchemical processing/analysis from start to finish. An interactive userinterface touch screen display device or a processor-based personalelectronic device such as an electronic pad (e.g. iPad, etc.),laptop/notebook, cell phone, or other may be provided which is operablyand communicably coupled to the system controller 2820 via communicationlink 5752. Such user interface devices are collectively represented anddesignated by reference numeral 5749 in the figures.

Referring to FIGS. 264-266, water filtration system 5751 may include influid communication and flow order an onboard raw water tank 5740, atleast one filter unit 5743, or optionally two filter units 5743 and5744, and a purified or filtered water tank 5741. These components maybe fluidly coupled together in a serial flow path as shown via suitableenclosed flow conduit 5746 which may be piping or tubing. Raw water tank5740 includes an inlet water fill port 5756 for filling the tank withwater from an available water source, and an outlet port fluidly coupledto the first filter unit 5743. The inlet port of filtered water tank5741 is fluidly coupled to second filter unit 5744 and the outlet portis fluidly coupled to the factory 5747 via flow conduit 5746. Thissection of flow conduit may include an openable/closeable valve 5745 tocontrol the supply and timing of filtered water to the factory.Similarly, another valve 5745 may be provided to regulate flow of rawwater to the train of filters 5743, 5744. The valves may be configuredfor an open position, closed position, and partially open or throttlepositions therebetween. Operation of the valving and the control of rawand filtered water may be automatically controlled by system controller2820 via communication links 5752 in some embodiments. One or both ofthe valves may be manually controlled in other implementations. A levelsensor 5753 operably and communicably coupled to the controller 2820 maybe mounted to filtered water tank 5741 which is operable to measure theliquid level in the tank in real time. Sensor 5753 controls the supplyand level of filtered water in tank 5741 available for the process. Whenthe level drops to a preprogrammed setpoint value, the controller mayopen the raw water valve 5745 to process and filter additional waterfrom raw water tank 5740 to replenish the support of filtered water inthe filtered water tank 5741.

Various other types of filtered water system sensors 5754 may beprovided which are linked to programmable system controller 2820 such asfor example without limitation unprocessed and processed water qualitysensors (e.g. resistivity/conductivity, temperature, etc.). Thesesensors may be located anywhere in the filtration system, including inthe tanks or flow conduits.

In some embodiments, the two-stage water filtration process shown may beused to produce highly purified water for the soil analysis system. Forexample, filter unit 5743 may be a particulate filter to remove sedimentand particulate matter suspended in the raw water. The second filterunit 5744 may be used to further refine water quality, and may be an ionexchange filter, or other filtration device such as without limitation areverse osmosis unit, UV purification unit, carbon filtration unit, etc.FIG. 267 shows an example of a particulate filter unit such as the typewhich may be used for filter unit 5743. Filter unit 5743 may include ahousing 5743-1 defining an internal cavity 5743-2 which contains aporous filter media 5743-3. The filter media may be cylindrical andtubular in shape in some embodiments. Any suitable filter media may beused, including paper, fabric, polymer, sintered metal, etc. Anysuitable flow path may be used internally within the filter housing.

In operation and flow sequence, water from raw water tank 5751 flowsthrough filters 5743 and 5744, and into the filtered/purified water tank5741. The filtered water is held in tank 5741 until demanded by thefactory 5747, at which time the system controller 2820 opens thenormally closed filtered water valve 5745 to provide filtered water (seedirectional water flow arrows).

In some embodiments as shown in FIG. 265, certain factory operations(e.g. component flushing/cleaning) may not require fully processed(filtered/purified) water and minimally filtered water may suffice. Inthis case, some water may bypass a portion of filtration train via abypass flow conduit 5755 and flow directly to the factory 5747 andbypass filter unit 5744. The bypass conduit may be automaticallycontrolled by controller 2820 which may be operably and communicablycoupled to bypass valve 5745 via communication link 5752. All otheraspects of the filtered water system 5751 shown in the presentembodiment with filtered water bypass are the same.

In some cases, the capacity of the filtered water tank 5741 may besufficient to meet the needs of an entire soil sampling and processingrun through the agricultural field. Accordingly, FIG. 266 shows anexample of a filtered water system without raw water tank 5740. In thiscase, raw water from an available source is provided to water fill port5746 via a suitable flow coupling and fluidly coupled via flow conduit5746 and raw water supply valve 5745 directly to filter unit 5743. Rawwater is immediately processed and filtered to fill filtered water tank5741 to capacity, which may have a larger volumetric capacity than thefiltered water tank used in the raw water batch processing modeembodiments previously described herein. All other aspects of thefiltered water system 5751 shown in the present embodiment without a rawwater tank are the same.

Alternative Centrifugation Apparatus for Supernatant Separation

In lieu of using pivotably movable or swinging centrifuge tubes 3450 inthe centrifuge 3400 assembly for separating the supernatant from thesoil slurry as previously described herein, FIGS. 268-280 depict analternative embodiment of a rotary supernatant extraction apparatus 5800for extracting the supernatant from the slurry using centrifugation. Inthe present embodiment, a disk-shaped fluid plate 5801 is provided whichis specially configured with a plurality of fluid passageways andchambers designed to perform the supernatant extraction with no movableparts (unlike tubes 3450) that move relative to the body of the plateitself, as further described below.

The rotary supernatant extraction apparatus 5800 has a generallydisk-shaped or “saucer-like” body and includes including an upper or topfluid plate 5801, lower or bottom clamping plate 5802, and anintermediate or inner gasket 5803 interspersed between the plates. Theplates and gasket may have a generally annular disk-shaped circularconfiguration for centrifugation with central openings 5801-3, 5802-3,and 5803-3 which may be coaxially aligned with rotational axis RA forpassage of the centrifuge drive shaft 3700 therethrough. This presentalternative assembly replaces the top and bottom covers 3520, 3521 thathold centrifuge tubes 3450 (see, e.g. FIGS. 67 and 76) and is mountedbelow and in selective fluid communication with the stationary fluidexchange manifold or dock 3430 at the same relative position in thecentrifuge 3400 as further shown in FIG. 53. The rotary hub 3500 coupledto the drive shaft 3700 is disposed between the fluid plate 5801 andclamping plate 5802, and passes completely through the gasket 5803 in acomplementary configured central through opening 5805. The spoke-shapedrotary hub 3500 with multiple radial projecting arms is interlockinglyengaged with the plate and gasket assembly to rotate the assembly viathe centrifuge for separating the supernatant from the soil slurry. Toaccomplish this, bottom surface 5801-2 of upper fluid plate 5801 and topsurface 5802-2 of the lower clamping plate 5802 each include a lockingrecess 5806, 5804 respectively which are complementary configured to andreceive the rotary hub 3500 and its radial spokes/arms as shown.Accordingly, locking recesses 5806, 5804, which extend partially throughthe thickness of the fluid and clamping plates 5801, 5802, may have aspoke shape and dimensions which generally corresponds to the shape anddimensions of the hub in the illustrated embodiment. When the plates arecoupled together, the rotary hub 3500 is thus locking into and trappedbetween the plates in the recesses. The inner gasket 5803 in turn istrapped as well between the plates. The rotary supernatant extractionapparatus 5800 is fixedly mounted to the main drive shaft 3700 andpiston support tube 3604 in a similar manner to top and bottom covers3520, 3521 of the centrifuge tube 3450 assembly, and movable upwards anddownwards with the shaft to dock and undock the extraction apparatus forcentrifugation of the soil slurry sample.

The fluid plate 5801 and clamping plate 5802 preferably may be made of apolymeric or plastic material in one embodiment for weight reduction,which may be injection molded or cast. The fluid plate 5801 may betransparent or translucent in some embodiments to allow visualinspection of the fluid and flow features in the plate further describedbelow for slurry sediment residue. In other possible embodiments, one orboth of the plates may be made of a preferably lightweight metallicmaterial.

Clamping plate 5802 has a disk shaped circular body including planarmajor top surface 5802-1 and opposing planar major bottom surface5802-2. The outer peripheral side 5802-4 of the plate may be verticaland planar as shown, or have a non-planar side profile. The top surfacemay be parallel to the bottom surface. The clamping plate 5802 has acircular central opening 5802-3 for receiving the centrifuge shafttherethrough.

Microfluidic processing disk 4000 is configured and operable to form adetachable fluid coupling to the fluid plate 8501 carried by the rotarytube hub 3500 through the intermediary stationary fluid exchange dock3430 of the centrifuge 3400, as previously described and shown herein.Fluid exchange dock 3430 is fluidly coupled and interposed between themicrofluidic processing disk 4000 mounted on top of the dock and fluidplate 8501.

With continuing general reference to FIGS. 268-280, fluid plate 5801 hasa disk shaped circular body including planar major top surface 5801-1and opposing planar major bottom surface 5801-2. The outer peripheralside 5801-4 of the plate may be vertical and planar as shown, or have anon-planar side profile. The top surface may be parallel to the bottomsurface. The bottom surface 5801-2 includes a plurality of speciallydesigned fluid passageways and enlarged reservoirs or chambers recessedinto the surface which extend partially through the top-to-bottomthickness of the fluid plate's body, but not penetrating its top surface5801-1 (best shown in FIGS. 270 and 276). The fluid passageways andchambers are grouped or clustered into a plurality of discretesupernatant separation features or devices 5807 configured to separateand extract the supernatant from the soil slurry via rotary centrifugalaction. Unlike the swinging centrifuge tubes 3450 which provide asimilar function, the rotational acceleration of the present rotarysupernatant extraction apparatus 5800 causes the fluid to flow bothradially and tangentially within the fluid passageways whencentrifugated whereas the centrifuge tubes produce primary inside tooutside radial fluid motion alone.

The supernatant separation devices 5807 are spaced circumferentiallyapart around the fluid plate 5801 and arranged symmetrically indifferent sectors of the fluid plate. This allows multiple soil samplesto be processed simultaneously in each device for different chemicalproperties/constituents in a single centrifugation cycle. Each separatedevice 5807 comprises a plurality of fluidly interconnected fluidpassageways 5808 and a sediment chamber 5809 configured and arranged toprovide the functions of separating and extracting the supernatant fromthe soil slurry fluid, and then flushing accumulated residual sedimentfrom the passageways and chamber after separation using preferablyfiltered water.

It bears particular noting that each chemical processing wedges 4002 ofmicrofluidic processing disk 4000 has its own dedicated andcorresponding supernatant separation device 5807 which is fluidlyisolated in fluid plate 8501 and the rotary supernatant extractionapparatus 5800 from every other flow element. When the processing disk4000 and supernatant extraction disk assembly are mounted in thecentrifuge 3400, the supernatant separation device 5807 associated witheach processing wedge 4002 is located directly beneath it and in fluidcommunication through the fluid ports in the stationary fluid exchangedock 3430 interposed between processing disk 4000 and rotary supernatantextraction apparatus 5800.

FIG. 271 shows the bottom surface of fluid plate 5801 with pluralsupernatant separation devices 5807 arranged in different sectors of thedisk-shaped plate. This figure shows four different examples andconfigurations of supernatant separation devices 5807A-D forconvenience, bearing in mind that the fluid plate 5801 may typicallycontain a plurality of supernatant separation devices of a singleconfiguration, or alternatively may include a combination of two or moredifferent device configurations. Each supernatant separation devicehowever has fluid elements in common albeit the specific configurationof those common elements may be different as seen.

Each supernatant separation device 5807A-D formed in the bottom of thetop fluid plate 5801 includes a fluidly interconnected cluster of fluidpassageways 5808 including a fluid inlet passageway 5808-1, fluid outletpassageway 5808-2, supernatant extraction passageway 5808-3, andsediment chamber 5809. Each passageway is fluidly connected separatelyto the sediment chamber and now to each other forming three discreteflow passages only fluidly interconnected via the sediment chamber, asshown. The passageways 5808 and sediment chamber 5809 are recessed intothe bottom surface 5801-2 of fluid plate 5801 and downwardly open beforethe fluid plate 5801 is assembled to gasket 5803 and bottom clampingplate 5802 (see, e.g. FIGS. 270 and 271). The passageways and sedimentchamber may be formed integrally with injection molding or casting ofthe fluid plate 5801, machining, or combinations thereof.

The fluid passageways 5808-1, 5808-2, and 5808-3 are elongatedstructures which may be in the form of channels or grooves in the fluidplate 5801. The passageways may each have a substantially uniformpolygonal or non-polygonal cross-sectional flow area in some embodimentswith corresponding generally uniform lateral width for a majority orsubstantially the entirety of their lengths. Other embodiments may varyin cross-section and/or width. The passageways are oriented and extendhorizontally along the bottom surface 5801-2 of fluid plate 5801.Preferably, the supernatant extraction passageway 5808-3 preferably hasa smaller width and/or cross-sectional flow area than the fluid inletpassageway 5808-1 and fluid outlet passageway 5808-2 to reduce thelikelihood of pulling sludge from sediment chamber 5809 when thesupernatant is extracted therefrom. The passageways each may have anon-linear

Each fluid passageway 5808-1, 5808-2, and 5808-3 of each supernatantseparation device 5807A-D in fluid plate 5801 has one end fluidlyconnected separately to sludge or sediment chamber 5809, and an oppositeend terminated with a vertical fluid port 5810-1, 5810-2, 5810-3 whichextends upwards through the fluid plate 5801 and penetrates its topsurface 5801-1 (see, e.g. FIG. 276) for fluid connection to mating portsformed in the stationary fluid exchange dock 3430 of centrifuge 3400.The layout or pattern of the ports in the fluid plate 5801 and dock 3430therefore match so each may become concentrically aligned when the fluidplate 5801 docks with the dock to exchange fluids (analogous in functionto that shown in FIG. 72 for covers 3520, 3521 in the pivotingcentrifuge tubes 3450 embodiment). The fluid passageways 5808-1, 5808-2,and 5808-3 each may have a non-linear circuitous configuration such thatthere is no straight line of sight between the ends connected to thesediment chamber 5809 and its respective vertical fluid port 5810-1,5810-2, 5810-3. However, it bears noting that each fluid passageway mayinclude linear/straight sections and angled or arcuately curved sectionsas shown in FIGS. 271-275. The fluid passageways are configured andarranged with respect to the sediment chamber 3809 to minimize entry ofthe remaining soil sludge or sediment into the passageways when thecentrifuge 3400 slows down and stops, thereby preferably retaining amajority of the sediment in its chamber.

The location of the vertical fluid ports 5810-1, 5810-2, 5810-3 of thefluid passageways 5808-1, 5808-2, and 5808-3 are predetermined anddesigned to optimize the performance and function of each port forextracting the supernatant from soil slurry sediment, exchanging fluidswith the fluid exchange dock 3430, and rinsing/cleaning the passagewaysand sediment chamber 5809 after each centrifugation cycle when therotary supernatant extraction apparatus 5800 is stationary and docket inthe centrifuge 3400. The port layout is therefore not random. In oneembodiment, each supernatant extraction fluid port 5810-3 is preferablypositioned closest to the center or axis of rotation RA of the rotarysupernatant extraction apparatus 5800 than the other vertical fluidports so that (1) it would be the least likely to get contaminated with“sloshing” sludge solution during centrifugation, and (2) becausematching the longest flow path of the supernatant extraction fluidpassageway with the cleanest fluid (i.e. clear supernatant) helps reducethe passageways that need rinsing and cleaning after each centrifugationcycle.

As the inverse of the supernatant extraction port 5810-3 being theradially innermost port, the outlet of high-density soil sediment wastefrom the sediment chamber 5809 of the centrifuge should preferably havethe shortest path length possible to minimize or prevent blockage.Accordingly, the fluid outlet port 5810-2 from the sediment chamber 5809may be the radially outermost port. The fluid inlet port 5810-1 maytherefore be the radial middle port between ports 5810-2 and 5810-3.Thought of one way, the vertical fluid ports are organized radiallyinward-to outward from cleanest to dirtiest or densest fluids handled.In other possible embodiments, however, the vertical fluid ports 5810-1,5810-2, 5810-3 may be at the same radial distance from the center oraxis of rotation RA of the rotary supernatant extraction apparatus 5800(which coincides with axis RA of the centrifuge 3400). In yet otherpossible embodiments, some or all of the fluid ports may be on thebottom or outer radial sides of the fluid plate 5801.

In some embodiments, each of the fluid ports 5810-1, 5810-2, 5810-3 maybe axially aligned with a radial centerline RC of each supernatantseparation device 5807A-D. This facilitates and simplifies the fluidexchange arrangement with mating clusters 3433 of flow passages 3434 inthe fluid exchange dock 3430 (see, e.g. FIGS. 55-56) for transferringfluid to and from the fluid plate 5801.

The sediment chamber 5809 is dimensionally larger than the passagewaysat least in maximum lateral width (measured transversely to therotational axis RA of the centrifuge 3400 in the plane of the rotarysupernatant extraction disk 5800, and greater in volumetric capacity toaccumulate sludge or sediment solids for separating the supernatantliquid out. Sediment chambers 5809 may have symmetric or asymmetricconfigurations selected to optimize the separation of supernatant fromthe soil slurry or fluid and deposition of the remaining sludge orsediment in the chamber. In some embodiments, as shown in FIGS. 272 to275, each sediment chamber 5809 may be located generally betweensupernatant extraction passageway 5808-3 and fluid inlet passageway5803-1 which have a generally radial orientation (allowing for portionswhich extend circumferentially). The sediment chambers 5809 may belocated preferably in the peripheral regions of the annular disk-shapedfluid plate 5801 beyond central locking recess 5806 nearer theperipheral sides 5801-4 than the central opening 5801-3 (see, e.g. FIG.271). The fluid ports 5810-1 to 5810-3 are preferably located radiallyinside the sediment chambers as shown. When the fluid plate 5801 iscentrifugated, the soil slurry will be driven radially outward bycentrifugal force such that the denser/heavier sludge or sedimentaccumulates in the outward region of each sediment chamber 5809 whilethe less dense/lighter clear supernatant accumulates in regions moreinwards thereof.

A brief description of the layouts/designs of fluid passageways andsediment chambers of the different example supernatant separation device5807 configurations disclosed herein will now be provided. FIG. 272shows a first embodiment of supernatant separation device 5807A alsoseen in FIG. 271. The layout provides long gentle arcuate curves foreasy rinsing and cleaning of the fluid passageways 5808-1 to 5808-3.During spin up of the centrifuge 3400, this layout provides a low-volumespillway (left of the radial centerline RC) for sloshing the soilslurry-supernatant mixture. During spin down, this design moreaggressively cradles the compacted sediment solids (left of “X”) frommoving and thus preventing fluid re-agitation of the sediment.

FIG. 273 shows a second embodiment of supernatant separation device5807B also seen in FIG. 271. During spin up, the slurry-supernatantmixture is cradled into the area of the sediment chamber 5809 marked“X”) and hold clear supernatant liquid to the right of and left ofradial centerline RC to prevent back flowing the supernatant out of thepassageways and ports.

FIG. 274 shows a third embodiment of supernatant separation device 5807Calso seen in FIG. 271. This layout is intended to: (1) be easy to fillthe passageways and sediment chamber with slurry and rinse/cleanoutafter centrifugation (note minimal number of corners or large spaces);(2) keep most of the clear supernatant fluid as close to the ports5810-1 to 5810-3 as possible (i.e. minimal pumping needed to extractsupernatant); and (3) during spin up, bias the slurry-supernatantmixture or solution from pushing radially inwards into the supernatantextraction passageway 5808-3.

FIG. 275 shows a fourth embodiment of supernatant separation device5807D also seen in FIG. 271. This layout is intended to: (1) during spinup of centrifuge 3400, bias the slurry-supernatant mixture/solution tothe left of the radial centerline RC to prevent pushing the slurrysolution out of fluid passageways and ports 5810-1 to 5810-3; (2) duringspin down, cradle the compacted sediment solids to the left of “X” toprevent remixing with the supernatant in supernatant extractionpassageway 5808-3; (3) provide plenty of relief spaced around the areaof compacted soil sediment particularly in sediment chamber 5809 foreasy rinsing/cleaning of the chamber and passageways.

In all of the embodiments of supernatant separation devices 5807A to5807D, it bears noting that supernatant extraction passageway 5808-3 andall ports 5810-1 to 5810-3 are radially inwards of the outermost portionof the sediment chambers 5809 to minimize chances of drawing theresidual sludge or sediment in the chambers out with the clearsupernatant.

To improve sealing of the fluid passageways 5808-1, 5808-2, and 5808-3and sediment chambers 5809 in the underside of fluid plate 5801 with thegasket 5803 when the plate assembly is coupled together, each passagewayand chamber may include a complementary configured raised sealing lip5811. Referring to FIGS. 277-279 which show the bottom surface 5801-2 offluid plate 5801, sealing lips 5811 outline and extend for the entireperimeter of the fluid passageways and chambers on all sides tocompletely seal them in a fluid tight manner when the gasket 5803 iscompressed against the fluid plate by the lower clamping plate 5802. Inone, the fluid plate 5801, clamping plate 5802, and gasket 5803 may becoupled and clamped together by a plurality of threaded fasteners 5812which are inserted through mounting holes 5813 formed in the plates andgasket (see, e.g. FIGS. 269-270). Holes 5813 in clamping plate 5802 maybe tapped and threaded to engage the fasteners. Other types of fastenersor mechanical coupling devices may be used, such as rivets, adhesives,ultrasonic welding, etc. The mounting holes 5813 may be arranged inrelatively close proximity to the fluid passageways and sedimentchambers to provide tight sealing thereof by the gasket.

In yet other embodiments, the lower clamping plate 5802 and gasket 5803may be eliminated the fluid passageways 5808 and sediment chambers 5809be may formed entirely internally within the fluid plate 5801 having asuitable thickness. This can be readily visualized with reference toFIG. 276 without need for further illustration by picturing the fluidpassageways and chambers disposed between, but not penetrating the topor bottom surfaces 5801-1, 5801-2 of fluid plate 5801 except for thefluid ports 5810-1, 5810-2, 5810-3.

Operation of the rotary supernatant extraction apparatus 5800 withsupernatant separation devices 5807 will now be briefly described. Theapparatus may include any of the supernatant separation device 5807A-Ddesigns described herein. The process or method for separatingsupernatant from a soil slurry mixture starts with apparatus 5800 in anupper position docked and fluidly coupled to fluid exchange dock 3430 toexchange fluids (analogously similar to that shown in FIG. 72 butsubstituting the rotary apparatus 5800 of the centrifuge tubes 3450).The supernatant and slurry mixture may be pumped by and transferredsimultaneously from the analysis processing wedges 4002 of microfluidicprocessing disk 4000 to the fluid inlet ports 5810-1 and fluid inletpassageways 5808-1 of each supernatant separation device 5807 in fluidplate 5801. The slurry mixture flows through each passageway 5808-1 intoits respective sediment chamber 5809. It bears noting that some slurrymixture may occupy portions of the various fluid passageways as well. Insystems which do not utilize the compact microfluidic processing disk4000, the slurry pump 3333 such as shown in FIG. 78 may pump the slurryand supernatant mixture to the rotary supernatant extraction apparatus5800. In this figure, it bears noting that the apparatus replaces thecentrifuge tubes 3450 of the centrifuge 3400.

Once the slurry mixture is transferred, the supernatant extractionapparatus 5800 is then lowered and undocked from the fluid exchange dock3430 of centrifuge 3400 (analogously similar to that shown in FIG. 73).The supernatant extraction apparatus 5800 is then rotated to separatethe clear supernatant from the slurry leaving behind concentrated solids(sludge or sediment) primarily in the sediment chamber 5809 (analogouslysimilar to that shown in FIGS. 74-75). During centrifugation, the solidswill be driven radially outwards into and accumulate in the outermostportions of the sediment chamber by centrifugal force. The clearsupernatant will accumulate radially inwards in the chamber.

The centrifuge 3400 is then stopped and the supernatant extractionapparatus 5800 is raised from its lower position upwards until itre-docks with fluid exchange dock 3430 in the first upper position(analogously similar to that shown in FIG. 72). The supernatant is thenextracted from the sediment chamber 5809 via the supernatant extractionpassageway 5808-3 and port 5810-3, then finally through the fluidexchange dock 3430 back to the sample processing system for chemicalanalysis of the supernatant. The supernatant pump 3312 in FIG. 78 forthat system or the transfer ump 4023 in FIG. 104 of the microfluidicprocessing disk 4000 based processing system may be used to draw thesupernatant out of the supernatant extraction apparatus 5800.

After the supernatant is withdrawn from the supernatant extractionapparatus 5800, the sediment chamber 5809 and fluid passageways 5808-1,5808-2, and 5808-3 are rinsed by injecting preferably filtered watertherethrough to remove the sludge/sediment and exhausted to waste. Thesupernatant extraction apparatus 5800 is now readied for the next slurrysample run.

It bears noting that the enclosed flow conduits shown and describedherein which interconnect the fluid system components may be rigid orflexible tubing or piping of suitable material including metallic ornon-metallic materials such as polymers. Some specific examples arementioned elsewhere herein.

According to another aspect of the invention, a vision system 6200 maybe provided to identify previous crop rows in the agricultural field andto quantify how much of soil sampled for soil testing comes from whatarea in the field. The system may further be employed to determine whereto collect soil samples based on any number of soil parameters such asorganic matter or other.

The vision system 6200 in one embodiment can comprise one or moredigital cameras 6201 that captures real-time images of the agriculturalfield during the soil sampling or other farming operations to determinewhere crop rows from prior plantings are located. The cameras 6201 maybe mounted on a self-propelled agricultural vehicle which may be atractor or sampling vehicle 5750 (see, e.g. FIG. 264), or an implementor device pulled or pushed through the field by an agricultural vehicleto capture real-time images of the field.

Digital images captured by the cameras 6201 may be relayed via suitablewired or wireless communication links 5752 to a central systemcontroller 2820 described herein for analysis as shown in FIG. 264, oranother CPU-based controller or monitor such as disclosed incommonly-owned U.S. Pat. No. 9,943,027, which is incorporated herein byreference. Such systems as disclosed in that patent are configured togenerate a soil map of the agricultural field which may be used todetermine where soil samples should be collected from in the field forchemical analysis according to the present disclosure. Such systems arecommercially available such as SmartFirmer™ from Precision Planting,LLC. The system can be used to keep increasing sampling density untilvariation between zones in the field is at “X” level setpoint which maybe preprogrammed into the controller or processor.

In some embodiments, soil sampling locations for chemical analysis canbe determined and selected based on measured organic matter amounts inthe field. An example of an implement that measures organic matter inthe field such as planting furrows and other soil parameters (e.g.temperature, moisture content, etc.) is the SmartFirmer™ which ismountable on the seed firmer or other agricultural implement or devicepulled through the soil as disclosed in the foregoing patent. The firmeris an angled device which travels through the furrow to ensure contactof the dispensed seed with the soil during planting (see, e.g. U.S. Pat.No. 9,943,027). It bears noting that the actual measured initial rawsoil moisture data associated with each soil sampling location may beutilized by the system controller 2820 to perform the volumizing andmassing operations previously described herein with respect to FIG. 284for determining the amount of water which needs to be added to thecollected soil for preparing a slurry meeting the preprogrammed desiredtarget water to soil ratio for chemical analysis.

Using the above technology, an initial soil sampling zone grid for afield can be planned. The grid can be adjusted to smaller zones untilthe differences between the zones is less than a selected amount (i.e.“X” level setpoint). This allows for zones to be changed actively duringthe soil sampling process to a resolution that minimizes differences.

Control System

FIG. 302 is a schematic system diagram showing the control or processingsystem 2800 including programmable processor-based central processingunit (CPU) or system controller 2820 as referenced to herein. Systemcontroller 2820 may include one or more processors, non-transitorytangible computer readable medium, programmable input/outputperipherals, and all other necessary electronic appurtenances normallyassociated with a fully functional processor-based controller. Controlsystem 2800, including controller 2820, is operably and communicablylinked to the different soil sample processing and analysis systems anddevices described elsewhere herein via suitable communication links tocontrol operation of those systems and device in a fully integrated andsequenced manner.

Referring to FIG. 302, the control system 2800 including programmablecontroller 2820 may be mounted on a translatable self-propelled orpulled machine 2802 (e.g., vehicle, tractor, combine harvester, etc.)which may include an agricultural implement 2840 (e.g., planter,cultivator, plough, sprayer, spreader, irrigation implement, etc.) inaccordance with one embodiment. In one example, the machine 2802performs operations of a tractor or vehicle that is coupled to animplement 2840 for agricultural operations. In other embodiments, thecontroller may be part of a stationary station or facility. The machine2802 and its boundaries are designated by dashed lines in the figure.Control system 2800, whether onboard or off-board machine 2802,generally includes the controller 2820, non-transitory tangible computeror machine accessible and readable medium such as memory 2805, and anetwork interface 2815. Computer or machine accessible and readablemedium may include any suitable volatile memory and non-volatile memoryor devices operably and communicably coupled to the processor(s). Anysuitable combination and types of volatile or non-volatile memory may beused including as examples, without limitation, random access memory(RAM) and various types thereof, read-only memory (ROM) and varioustypes thereof, hard disks, solid-state drives, flash memory, or othermemory and devices which may be written to and/or read by the processoroperably connected to the medium. Both the volatile memory and thenon-volatile memory may be used for storing the program instructions orsoftware. In one embodiment, the computer or machine accessible andreadable non-transitory medium (e.g., memory 2805) contains executablecomputer program instructions which when executed by the systemcontroller 2820 cause the system to perform operations or methods of thepresent disclosure including measuring properties and testing of soiland vegetative samples. While the machine accessible and readablenon-transitory medium (e.g., memory 2805) is shown in an exemplaryembodiment to be a single medium, the term should be taken to include asingle medium or multiple media (e.g., a centralized or distributeddatabase, and/or associated caches and servers) that store the one ormore sets of control logic or instructions. The term “machine accessibleand readable non-transitory medium” shall also be taken to include anymedium that is capable of storing, encoding or carrying a set ofinstructions for execution by the machine and that cause the machine toperform any one or more of the methodologies of the present disclosure.The term “machine accessible and readable non-transitory medium” shallaccordingly also be taken to include, but not be limited to, solid-statememories, optical and magnetic media, and carrier wave signals.

Network interface 2815 communicates with the soil sample processing andanalysis systems and devices described elsewhere (collectivelydesignated 2803 in FIG. 302), and other systems or devices which mayinclude without limitation implement 2840 having its own controllers anddevices, and the machine network 2810 of the machine 2802 (e.g., acontroller area network (CAN) serial bus protocol network, an ISOBUSnetwork, etc.).

The machine network 2810 can include sensors 2812 (e.g., sensors formeasuring properties of soil and vegetative samples, speed sensors,etc.), controllers 2811 (e.g., GPS receiver, radar unit) for controllingand monitoring operations of the machine or implement, and soil samplecollection system 2801. The network interface 2815 can be configured forwired and/or wireless bidirectional communications which may include atleast one of a GPS transceiver, a WLAN transceiver (e.g., WiFi), aninfrared transceiver, a Bluetooth transceiver, Ethernet, Near FieldCommunications, or other suitable communication interfaces and protocolsfor communications with the other devices and systems including theimplement 2840. The network interface 2815 may be integrated with thecontrol system 2800 as illustrated in FIG. 302, the machine network2810, implement 2840, or elsewhere. The I/O (input/output) ports 2829 ofcontrol system 2800 (e.g., diagnostic/on board diagnostic (OBD) port)enable communication with another data processing system or device(e.g., display devices, sensors, etc.).

The programmable controller 2820 may include one or moremicroprocessors, processors, a system on a chip (integrated circuit),one or more microcontrollers, or combinations thereof. The processingsystem includes processing logic 2826 for executing softwareinstructions of one or more programs and a communication module or unit2828 (e.g., transmitter, transceiver) for transmitting and receivingcommunications from the machine 2802 via machine network 2810, ornetwork interface 2815, or implement 2840 via implement network 2850.The communication unit 2828 may be integrated with the control system2800 (e.g. controller 2820) or separate from the processing system. Inone embodiment, the communication unit 2828 may be in operable datacommunication with the machine network 2810 and implement network 2850via a diagnostic/OBD port of the I/O ports 2829.

Programmable processing logic 2826 of the control system 2800 whichdirects the operation of system controller 2820 including one or moreprocessors may process the communications received from thecommunication unit 2828 or network interface 2815 including agriculturaldata (e.g., test data, testing results, GPS data, liquid applicationdata, flow rates, etc.), and soil sample processing and analysis systemsand devices 2803 data. The memory 2805 of control system 2800 isconfigured for preprogrammed variable or setpoint/baseline values,storing collected data, and computer instructions or programs forexecution (e.g. software 2806) used to control operation of thecontroller 2820. The memory 2805 can store, for example, softwarecomponents such as testing software for analysis of soil and vegetationsamples for performing operations of the present disclosure, or anyother software application or module, images 2808 (e.g., captured imagesof crops), alerts, maps, etc. The system 2800 can also include an audioinput/output subsystem (not shown) which may include a microphone and aspeaker for, for example, receiving and sending voice commands or foruser authentication or authorization (e.g., biometrics).

In the embodiments with sampling system 2801 (e.g., processing system2801), vehicle 2802 (e.g., machine 2802) can further include a sensingsystem 2812 or be coupled to an implement 2840 that includes a sensingsystem 2852. The sensing systems (e.g., sensing system 2812, sensingsystem 2852) are in data communication with system controller 2820.Additional data at each point sampled can be tested by the sensingsystem. Sensing systems can include one or more of the following:spectrographic measurement, electrical conductivity, apparent electricalconductivity, LIDAR, radar, ground penetrating radar, sonar, opticalheight, camera, time of flight camera. Examples of spectrographicmeasurement include, but are not limited to, visible light, laser,near-infrared, infrared, transient infrared spectroscopy, RAMANspectroscopy, ultraviolet, and x-ray. The combination of soil and/orvegetation sampling along with sensing can provide a more detailedanalysis of the conditions in the field.

The system controller 2820 communicates bi-directionally with memory2805 via communication link 2830, machine network 2810 via communicationlink 2831 and or alternatively via communication link 2837, networkinterface 2815 via communication link 2832, display devices 2830 andoptionally a second display device 2825 via communication links 2834,2835, and I/O ports 2829 via communication links 2836. System controller2820 further communicates with the soil sample processing and analysissystems and devices 2803 via the wired/wireless communication links 5752previously described herein via the network interface 2815 and/ordirectly as shown.

Display devices 2825 and 2830 can provide visual user interfaces for auser or operator. The display devices may include display controllers.In one embodiment, the display device 2825 is a portable tablet deviceor computing device with a touchscreen that displays data (e.g., testresults of soil, test results of vegetation, liquid application data,captured images, localized view map layer, high definition field maps ofas-applied liquid application data, as-planted or as-harvested data orother agricultural variables or parameters, yield maps, alerts, etc.)and data generated by an agricultural data analysis software applicationand receives input from the user or operator for an exploded view of aregion of a field, monitoring and controlling field operations. Theoperations may include configuration of the machine or implement,reporting of data, control of the machine or implement including sensorsand controllers, and storage of the data generated. The display device2830 may be a display (e.g., display provided by an original equipmentmanufacturer (OEM)) that displays images and data for a localized viewmap layer, as-applied liquid application data, as-planted oras-harvested data, yield data, controlling a machine (e.g., planter,tractor, combine, sprayer, etc.), steering the machine, and monitoringthe machine or an implement (e.g., planter, combine, sprayer, etc.) thatis connected to the machine with sensors and controllers located on themachine or implement.

The implement 2840 (e.g., planter, cultivator, plough, sprayer,spreader, irrigation implement, etc.) may include its own implementnetwork 2850, a processing system 2862, a network interface 2860, andoptional input/output ports 2866 for communicating with other systems ordevices including the machine 2802. In one example, the implementnetwork 2850 (e.g., a controller area network (CAN) serial bus protocolnetwork, an ISOBUS network, etc.) includes a pump 2856 for pumpingliquid from a storage tank(s) 2890 to control monitoring units (CMUs)2880, 2881, . . . N of the implement, sensors or sensing system 2852(e.g., soil sensors, vegetation sensors, soil probe, speed sensors, seedsensors for detecting passage of seed, downforce sensors, actuatorvalves, OEM sensors, flow sensors, etc.), controllers 2854 (e.g., GPSreceiver), and the processing system 2862 for controlling and monitoringoperations of the machine. The CMUs control and monitor the applicationof the liquid to crops or soil as applied by the implement. The liquidapplication can be applied at any stage of crop development includingwithin a planting trench upon planting of seeds, adjacent to a plantingtrench in a separate trench, or in a region that is nearby to theplanting region (e.g., between rows of corn or soybeans) having seeds orcrop growth. Alternatively, solids can be applied via the spreader.

The implement processing system 2862 communicates bi-directionally withthe implement network 2850, network interface 2860, and I/O ports 2866via communication links 2841-2843, respectively. The implement 2840communicates with the machine network 2810 via wired and/or wirelessbi-directional communications 2804. The implement network 2850 maycommunicate directly with the machine network 2810 or via the networksinterfaces 2815 and 2860. The implement 2840 may also be physicallycoupled to the machine 2802 as indicated in FIG. 302 for agriculturaloperations (e.g., planting, harvesting, spraying, etc.).

While the foregoing description and drawings represent some examplesystems, it will be understood that various additions, modifications andsubstitutions may be made therein without departing from the spirit andscope and range of equivalents of the accompanying claims. Inparticular, it will be clear to those skilled in the art that thepresent invention may be embodied in other forms, structures,arrangements, proportions, sizes, and with other elements, materials,and components, without departing from the spirit or essentialcharacteristics thereof. In addition, numerous variations in themethods/processes described herein may be made. One skilled in the artwill further appreciate that the invention may be used with manymodifications of structure, arrangement, proportions, sizes, materials,and components and otherwise, used in the practice of the invention,which are particularly adapted to specific environments and operativerequirements without departing from the principles of the presentinvention. The presently disclosed embodiments are therefore to beconsidered in all respects as illustrative and not restrictive, thescope of the invention being defined by the appended claims andequivalents thereof, and not limited to the foregoing description orembodiments. Rather, the appended claims should be construed broadly, toinclude other variants and embodiments of the invention, which may bemade by those skilled in the art without departing from the scope andrange of equivalents of the invention.

1. A separation device for extracting a test material from anagricultural slurry, the device comprising: a support housing; a fluidexchange dock fixedly mounted to the housing, the fluid exchange dockcomprising a top surface, a bottom surface, and a plurality of flowpassages extending between the top surface and bottom surface; a motordrive mechanism; a rotary tube hub coupled to the motor drive mechanism,the tube hub rotatable via operation of the motor drive mechanism; aplurality of centrifuge tubes pivotably mounted to the tube hub, each ofthe centrifuge tubes comprising a plurality of fluid conduits eachhaving a respective port arranged on a top surface of the centrifugetube, wherein the centrifuge tubes are cleanable and reusable.
 2. Theseparation device according to claim 1, wherein the fluid exchange dock,the rotary tube hub, or both the fluid exchange dock and rotary tube hubis movable between a docked position such that the fluid exchange dockand rotary tube hub are adjacent and an undocked position such that thefluid exchange dock and rotary tube hub are not adjacent, and whereinwhen the tube hub is in the docked position, a fluid passageway isformed between each of the flow passages of the fluid exchange dock anda corresponding one of the fluid conduits in the centrifuge tubes. 3.The separation device according to claim 1, wherein the ports on the topsurface of each centrifuge tube are arranged in cluster pattern whichcoincides with a corresponding cluster pattern of fluid passagewaysformed in the bottom surface of the fluid exchange dock.
 4. Theseparation device according to claim 1, wherein the fluid conduits ofeach centrifuge tube are arranged to receive slurry via the fluidexchange dock, and wherein the fluid conduits are configured to separatea test material from the slurry when the rotatory hub is rotated in theundocked position.
 5. The separation device according to claim 2,wherein the fluid conduits of each centrifuge tube are arranged toreceive slurry via the fluid exchange dock, and wherein the fluidconduits are configured to separate a test material from the slurry whenthe rotatory hub is rotated in the undocked position.
 6. The separationdevice according to claim 3, wherein the fluid conduits of eachcentrifuge tube are arranged to receive slurry via the fluid exchangedock, and wherein the fluid conduits are configured to separate a testmaterial from the slurry when the rotatory hub is rotated in theundocked position.
 7. The separation device according to claim 1,wherein the centrifuge tubes are in a vertical orientation when the tubehub is not rotated, and a horizontal orientation when the tube hub isrotated via pivotable movement of each centrifuge tube.
 8. Theseparation device according to claim 2, wherein the centrifuge tubes arein a vertical orientation when the tube hub is not rotated, and ahorizontal orientation when the tube hub is rotated via pivotablemovement of each centrifuge tube.
 9. The separation device according toclaim 3, wherein the centrifuge tubes are in a vertical orientation whenthe tube hub is not rotated, and a horizontal orientation when the tubehub is rotated via pivotable movement of each centrifuge tube.
 10. Theseparation device according to claim 4, wherein the centrifuge tubes arein a vertical orientation when the tube hub is not rotated, and ahorizontal orientation when the tube hub is rotated via pivotablemovement of each centrifuge tube.
 11. The separation device according toclaim 7, further comprising an upper cover and a lower cover coupled tothe tube hub, each of the covers comprising a plurality of cutouts eachconfigured to receive a corresponding centrifuge tube when in thehorizontal orientation.
 12. The separation device according to claim 8,further comprising an upper cover and a lower cover coupled to the tubehub, each of the covers comprising a plurality of cutouts eachconfigured to receive a corresponding centrifuge tube when in thehorizontal orientation.
 13. The separation device according to claim 9,further comprising an upper cover and a lower cover coupled to the tubehub, each of the covers comprising a plurality of cutouts eachconfigured to receive a corresponding centrifuge tube when in thehorizontal orientation.
 14. The separation device according to claim 10,further comprising an upper cover and a lower cover coupled to the tubehub, each of the covers comprising a plurality of cutouts eachconfigured to receive a corresponding centrifuge tube when in thehorizontal orientation.
 15. The separation device according to claim 1,wherein the drive mechanism comprises a larger main motor configured torotate the rotatory hub at high speed for centrifugating the slurry, anda smaller indexing motor to incrementally rotate the tube hub at a lowspeed to align the centrifuge tubes with the flow passages of the fluidexchange dock.
 16. The separation device according to claim 15, whereinthe drive mechanism further comprises a gear train coupling each of themain and indexing motors to a drive shaft coupled to the tube hub.